LIPUS: An Effective Alternate Option to Treat Nonunions of Fractures and Surgical Fusions in Trauma and Orthopaedic Surgery

Abstract

Background: Limited studies have been conducted to evaluate the use of exogen in different patient groups. We aim to determine the rate of radiological union and symptom resolution following use of Low Intensity Pulsed Ultrasound (LIPUS) therapy, to analyse the efficacy of LIPUS therapy in comparable patient groups, and to determine the cost effectiveness of LIPUS therapy.
Materials and Methods: 32 adult patients with nonunions of fractures and surgical fusions who were treated with LIPUS over 3 years were identified from the clinic database. Data were recorded retrospectively. Patients were divided into 3 subcategories to provide a meaningful analysis of comparable groups: foot and ankle versus other regions, surgical versus conservative management, and atrophic versus hypertrophic nonunion. A statistical calculator was employed for statistical analysis.
Results: Clinical symptoms of nonunion resolved in 19 (59%) patients and radiological union was achieved in 18 (56%) patients post LIPUS use. The foot and ankle group demonstrated the best outcome, with union rates of 73% when compared to other fractures at 44% union. Significant potential cost savings of £3150 per patient have been calculated (p=0.006) when compared to surgical management of nonunion.
Discussion: Overall, we achieved just under 60% resolution of clinical symptoms and/or radiological improvement, without the need for further intervention. In our study we observed particularly better outcomes in the foot and ankle group compared to other fractures; this could provide guidance for future targeting of LIPUS therapy to specific patient cohorts based on their anatomical regions of nonunion.

Full text

16
Archives of Orthopedics and Rheumatology V4 . I1. 2021
Introduction
The healing of bone following fractures and surgical
fusion procedures is a complex biomechanical
process[1]. Around 98% of fractures undergo primary
      
      
     


and socioeconomic burden. It also poses considerable

 
the treatm
There are several treatment options available for
      
       

     
   
potential for further complications[7]. In an attempt
      
options have emer
Archives of Orthopedics and Rheumatology
ISSN: 2639-3654 | Volume 4, Issue 1, 2021
DOI: https://doi.org/10.22259/2638-3654.0401003
LIPUS: An Effective Alternate Option to Treat Nonunions
of Fractures and Surgical Fusions in Trauma and
Orthopaedic Surgery
Maria Nowicka1, Darren Marshall2, Haroon Majeed3*
12
3

*Corresponding Author:
Haroon Majeed, 
Manchester Foundation Trust, UK.
Abstract
Background: Limited studies have been conducted to evaluate the use of exogen in different patient groups. We
aim to determine the rate of radiological union and symptom resolution following use of Low Intensity Pulsed
            
determine the cost effectiveness of LIPUS therapy.
Materials and Methods: 32 adult patients with nonunions of fractures and surgical fusions who were treated

were divided into 3 subcategories to provide a meaningful analysis of comparable groups: foot and ankle
versus other regions, surgical versus conservative management, and atrophic versus hypertrophic nonunion. A
statistical calculator was employed for statistical analysis.
Results: Clinical symptoms of nonunion resolved in 19 (59%) patients and radiological union was achieved in
18 (56%) patients post LIPUS use. The foot and ankle group demonstrated the best outcome, with union rates


Discussion:            
improvement, without the need for further intervention. In our study we observed particularly better outcomes
in the foot and ankle group compared to other fractures; this could provide guidance for future targeting of

Keywords: LIPUS; Exogen; Fracture; Nonunion

17 Archives of Orthopedics and Rheumatology V4 . I1. 2021

      
     
       
  
healing.
       
      
in micromechanical stress. This mechanical stress
transiently increases the membrane expression of


     
maturation of osteoblasts and results in endochondral

       
  

surgical fusions in trauma and orthopaedic surgery.
Material and Methods
        
       
to September      
     
     
 
      
    
      
     
       
     
     
complications following therapy or further treatments

      
     
order to provide a meaningful analysis of comparable
      
subcategories:
 
 
 
A statistical calculator was employed for statistical
analysis. Categorical data were analysed using the
     
included clinical resolution of symptoms and presence
     

 
test was used to calculate the p value. The p value

analysis.
Results
      
included in the analysis. There were 14 (44%) male
        
       
      
undergone elective joint fusion surgery. The list of

       
amongst the cohort. The average nonunion gap was
     
plain radiographs or the computed tomography (CT)
scans at the time of establishing the diagnosis of
nonunion.
LIPUS: An Effective Alternate Option to Treat Nonunions of Fractures and Surgical Fusions in Trauma
and Orthopaedic Surgery
Table1. List of diagnoses amongst patient cohort
Diagnosis Number of cases
Subtalar fusion 
 
1st 1
 
 
 
 1
 
 
 
 
 
 1

18
Archives of Orthopedics and Rheumatology V4 . I1. 2021
       
resolution and demonstrated radiological union on



       
symptoms as well as radiological union following

The interval from the initial fracture or primary
surgical procedure until a diagnosis of nonunion was
suspected or established was less than 6 months in 16


was performed to evaluate the relationship between time
to diagnosis of nonunion against the average duration
      

        
persisting symptoms and no radiological progression of
union. 7 of these patients underwent revision surgery.


      
        
   
     
surgery could go ahead. The other patient refused
to undergo surgery as the residual symptoms were
       

LIPUS: An Effective Alternate Option to Treat Nonunions of Fractures and Surgical Fusions in Trauma
and Orthopaedic Surgery
The average time from injury or surgery to the time of


      

        
in their medical notes. The average duration of use of


     
         
        

        


Table2. Comparison of duration of treatment, symptom resolution, and radiological union in time to diagnosis of
nonunion groups.
Time to diagnose
nonunion
Number of cases
(%)
Average duration of
treatment in weeks
Symptom
resolution (%)
Radiological
union (%)
<6 months    
>6 to 8 months    
>9 months    
p value  
Table3. Comparison of duration of treatment, symptom resolution, and radiological union in the subgroup
analysis
Number of cases
(%)
Average duration of
Exogen used in weeks
Symptom
resolution (%)
Radiological
union (%)

nonunions
 16 11 (69) 
Other fractures  19  7 (44)
P value   
Surgical
management
14 (44)   
Conservative
management
 18 11 (61) 
P value   
Atrophic  16  
Hypertrophic  19 9 (69) 
P value   

19 Archives of Orthopedics and Rheumatology V4 . I1. 2021
LIPUS: An Effective Alternate Option to Treat Nonunions of Fractures and Surgical Fusions in Trauma
and Orthopaedic Surgery
     
       
       
         
some resolution of symptoms without any further

       
reported persisting symptoms. They both were
suspected to have developed an adverse reaction to
       
      
        



t       

  
Ten (67%) patients had atrophic nonunion. There

failed treatment group.
      
      
fusions versus other regions; fractures managed
surgically versus conservatively; and atrophic versus
    

     
      
the results of this analysis.
Table 4.
Diagnosis Initial
treatment
Revision surgery Smoking status Radiological appearances
of nonunion

comminuted fracture


  Hypertrophic
Humeral shaft fracture Conservative in

  Atrophic

fracture
   Hypertrophic
Humeral shaft fracture Humeral brace 

 Hypertrophic

fracture
   Atrophic
Humeral shaft
comminuted fracture
Humeral brace   Hypertrophic

osteoarthritis
Conservative in


fusion
 Atrophic
Fig1. Symptom resolution and radiological union in each subgroup

20
Archives of Orthopedics and Rheumatology V4 . I1. 2021
Discussion

   
demonstrates the rates of symptomatic resolution and
fracture union in the subgroups which are discussed
below in more detail.
Foot and Ankle Vs other Regions
       
      
  
regions (p      
      
radiological and symptomatic union following the
 reported a similar

rate of union in upper limb fractures compared to the

hypothesis to explain this trend considers the inherent

maintain stability of a humeral fracture and allow for
     

       
suggesting there may be an issue with the stability of

therapy.
Another contributing factor is the potential impact
    
   
         
        
the target area without any divergence of the waves.

than other regions of the body where the presence
of excessive soft tissue may potentially lower the
       




Hypertrophic vs Atrophic
        
     
      
  p   
demonstrated a greater proportion of symptom
resolution in comparison to the atrophic group (69%
p 
       
       
atrophic nonunions.

of blood vessels in comparison to normal healing
groups and may also be characterised by dysfunctional
mesenchymal stem cells at the fracture site[16].
These factors may explain relatively poor outcomes of

the hypertrophic nonunions reported in the literature.
Although in our study radiological union rates were
        
      

et al[17] who found that hypertrophic nonunions
 
      
associated with atrophic nonunion has further been
demonstrated by Watanabe et al[18]. Among a group
        
  p     
        
hypertrophic nonunion. Atrophic nonunion may
    

      
secondary to problems with mechanical instability.
        
of hypertrophic nonunions as it does not address the
underlying mechanical instability theorised to cause
a hypertrophic nonunion; further research could be
conducted to evaluate this.
Conservative vs Surgical Management
      
conservatively prior to developing nonunion and the
remainder had nonunion following their primary
surgical procedures. The conservatively managed
group showed improved radiological union rates
      
p
resolution rates were similar between the two groups
    p 
      
both such groups. Hemery et al[19] presented a 79%
success rate in a case series of 14 patients with femoral
LIPUS: An Effective Alternate Option to Treat Nonunions of Fractures and Surgical Fusions in Trauma
and Orthopaedic Surgery

21 Archives of Orthopedics and Rheumatology V4 . I1. 2021
Cost Implications
Cost analysis was performed on these patients who
     
estimates the average cost saving associated with
eliminating the need for revision surgery in those
 The

patient for the duration of its usage. This was compared
against the potential cost of revision surgery that

nonunion and the type of revision surgery that could


        
  

        
LIPUS: An Effective Alternate Option to Treat Nonunions of Fractures and Surgical Fusions in Trauma
and Orthopaedic Surgery
and tibial fracture nonunions managed surgically.
         
       
      

       
both conservatively managed and surgically managed
nonunion.
2a 2b
Fig2 (a & b). 
after the base of 5th metatarsal fracture (2a). Treated with Exogen for 4 months that led to complete resolution
of symptoms and radiological union (2b).
3a 3b 3c
Fig7 (a, b & c). 

Treated with Exogen for 4 months that led to complete resolution of clinical symptoms and radiological
progression to union (3c).

22
Archives of Orthopedics and Rheumatology V4 . I1. 2021
     
to potential surgery (p    
       
       
considered safe and has no potential complications or

Strengths and limitations
The main strength of our study is an elaborated
      
     
       
This could provide guidance for future targeting of
      
their anatomical regions of nonunion.
wledge limitations of our study. The study
  
      
       
        
     


      
   
       established
nonunions in fractures and fusion procedures in
         


to treat these patients.
References
      [1]
     

     
      
       


  
Health economics: a cost analysis of treatment
     


[4]
      
    

      
complex tibial and femoral nonunion using the



       [6]
Treatment of nonunions and osseous defects
with bone graft and calcium sulfate. Clin Orthop
   

       [7]
        
      
      
fracture nonunions: a retrospective cohort
        

[8]
      
   

       [9]
       
    
     

      
    
      

      [11]
      


     
    

 



   
i

LIPUS: An Effective Alternate Option to Treat Nonunions of Fractures and Surgical Fusions in Trauma
and Orthopaedic Surgery

23 Archives of Orthopedics and Rheumatology V4 . I1. 2021

use of low intensity pulsed ultrasound for bone


       [14]





 

[16]
     
    

[17]
       
    
  
    

       [18]
 
    
ultrasound for delayed unions and nonunions:
      


  [19]

     
     

    
    
     

     
     
     


LIPUS: An Effective Alternate Option to Treat Nonunions of Fractures and Surgical Fusions in Trauma
and Orthopaedic Surgery
Citation: Maria Nowicka, Darren Marshall, Haroon Majeed. LIPUS: An Effective Alternate Option to Treat
Nonunions of Fractures and Surgical Fusions in Trauma and Orthopaedic Surgery. Archives of Orthopedics and
. 
Copyright:   Maria Nowicka, Darren Marshall, Haroon Majeed. This is an open access article
distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.