Employment in the Australian Army after Anterior Cruciate Ligament Reconstruction – A Pilot Study of 3 Year Postoperative Outcomes

In   Issue .

CAPT Peter Weinrauch M.B.B.S. (Qld)

COL Peter Sharwood RFD. M.B.B.S.(Qld), F.R.A.C.S. F.A.Orth.A.b

ABSTRACT

This study examines the military employment of soldiers in the Australian Regular Army 3 years after Anterior Cruciate Ligament (ACL) reconstruction. Patients undertaking ACL reconstruction were more likely to be assessed as medically unfit for military service compared to a control group undertaking  an unrelated procedure (extraction of wisdom teeth), however overall discharge  rates were not affected. 71 % of patients undertaking ACL reconstructions were considered  fit for military service 3 years after surgery. allowing their participation in active operational duty.

 

INTRODUCTION

Injuries sustained during training or sports represent a substantial  health problem within the Australian Defence Force (ADF), resulting in significant  casualty rates and reduced employment capability.’ For military patients sustaining tears of the Anterior Cruciate Ligament (ACL), non operative  management  has been associated with reduced occupational capacity and lower rates of return to unrestricted  military service compared to operative management.2 Bellmontetal. (1999) demonstrated 94.3% of U.S. Army Aviators post ACL reconstruction returned to service with only 2.3% requiring medical discharge after primary reconstruction.3 Edwards etal. in a retrospective review of active duty military patients 2.35 years after ACL reconstruction however found only 78/ 112 (78%)  had returned to full unrestricted service.4 Cullisonetal. similarly demonstrated the rate of medical discharge 29 months after autogenous  patella tendon ACL reconstruction to be 23%.2  Revision ACL reconstruction is associated  with inferior outcomes for military employment, with only 60% of U.S Army Aviators returning to service.3 The  impact of ACL rupture on future military employment and prediction of employability  in the Australian Defence  Force (ADF)  after reconstruction has to date  not been assessed. This pilot study retrospectively examines the employment  of soldiers in the Australian Regular Army 3 years after ACL reconstruction.

PATIENTS  AND METHODS

The study group consisted of all patients who underwent primary ACL reconstruction at 2 Health Services Battalion between July 1 997 and September l 999 identi fied retrospectively from operation logbooks. Only male patients serving  full time in the Australi an Regular Army (ARA) at the time of operation were included. 38 patients satisfied  these criteria for inclusion in the study. The operations were performed by 4 Orthopaedic Surgeons utilising either autogenous patella  tendon or hamstring graft according to surgeon preference and individual patient assessment. Adjunctive arthroscopic procedures such as chondroplasty, meniscal repair or partial meniscectomy were performed where indicated during ACL reconstruction.

The control group consisted of 40 consecutive patients who underwent an unrelated  procedure (dental extraction) at the same hospital between July 1997 and October 1997. The same inclusion criteria were applied to the control group.

The study  protocol was granted approval by the Australian Defence  Human Research  Ethics Committee (ADHREC) prior to data collection. Preoperative  Medical Employment  Classificat ion (MEC) Scores effective Jul y 1997  were retrospectively obtained from the Army Health Records Department. Current MEC scores for patients still serving  in the Australian Defence  Force or MEC on discharge was similarly obtained. The current military employment status of all patients was determined by database  review.

RESULTS

Table l  provides an overview of the results obtained. The average time to follow up was 3.4 +10.75  years in the ACL Group and 4. 35 +10.05  years in the Control Group. At final  review. equivalent numbers  of patients from both groups  remained within active military service (20/ 38 ACL Group; 2 1 I 40 Control Group). and an equal number of patients had discharged  (7/ 38 ACL Group; 7/40 Control  Group).

10/ 38 (26%)  patients in the ACL group and 2/40 (5%) patients in the Control group at final review were considered  unfit for military service on medical grounds, and had been discharged or were in process of discharge (p<0.02; Fisher Exact Test). 27/ 38 (71 %) of the ACL Group and 38/ 40 (95%) of the Control Group were considered on medical grounds to be fit for military service, including active operational deployment. Two patients who were previously considered unfit for military service on medical grounds  prior to ACL reconstruction were assessed as fit for service at final review.

No patients were lost to follow-up.

Table can be found in the full download of this edition

DISCUSSION

The results of this study demonstrate  that patients with ACL deficient knees are at 3 years post reconstruction more likely to be assessed as medically unfit for military service compared to the control group selected. The correlation  between ACL reconstruction and medical fitness observed  in this study does not however directly establish a cause and effect relationship as patients are often assessed as unsuitable for military service  on the grounds of greater than one condition. and review of the discharge medical examination findings was not conducted.

ACL reconstruction has not been demonstrated to result in an increase in the overall  rate of discharge from active  military service. The majority (71%) of patients undertaking ACL reconstruction were considered fit for military service 3 years postoperatively, allowing their pm1icipation in active operational duty if required.

It should be understood that the results of this study relate only to patients who have undertaken ACL reconstruction. and the employment outcomes for military patients with ACL deficient knees managed non-operatively has not been assessed. Limitations of this study include the small number of subjects evaluated  and the retrospective methodology.

This study provides a pilot for the conduct of a comprehensive prospective trial into the employment outcomes after ACL rupture in the Australian Defence Force.

 

The authors  wish to acknowledge the advice  prov ided by Lt Col Turner in preparation of the manuscript. References
  1. Directorate of Preventi ve Health. ADF Health Status. Canberra: Defence Publ ishing Service; 2000.
  2. CULLISON. TR.. O'BRIEN.T 1.. GETKA. K. & JONSON. S. Anterior Cruciate Ligament Reconstruction  in the Military  Patient.  Mi litary Medicine 1998; 163( I ): 1 7- 19.
  3. BELMONT, P. J., SHAWEN, S. B.. MASON. K. T & SLADICKA. S. I. Incidence and Outcomes of Anterior
Cruciate Ligament Reconstruction among U.S. Army Aviators. Aviat Space Environ Med 1999; 70(4): 31 6- 320.
  1. EDWARDS. K. J.. HAY. R. M., GORAL, A. B. & KELSO, T Functional Restoration Following Anterior
Cruciate Ligament Reconstruction in Active-Duty  Military PersonneL Military Medicine 1991; 156(3): 1 18 - 1 21.