Non-surgical management of ankle contracture following acquired brain injury

BACKGROUND AND PURPOSE

The purpose of this study was to document the outcome of non-surgical management of equinovarus ankle contracture in a cohort of patients with acquired brain injury admitted to a specialist Neurosurgical Rehabilitation Unit.

METHODS

This prospective descriptive study examined all patients with a new diagnosis of moderate to severe acquired brain injury (Glasgow Coma Scale score </=12) admitted for rehabilitation over a 1 year period. Ankle dorsiflexion range and plantarflexor/invertor muscle activity were evaluated weekly during the period of hospitalization. Contracture was defined as maximal passive range of motion </= 0 degrees dorsiflexion, with the knee extended, on a minimum of two measurement occasions. Patients were retrospectively allocated to one of four treatment outcome categories according to ankle dorsiflexion range, type of intervention required and response to treatment.

RESULTS

Ankle contracture was identified in 40 of the 105 patients studied. Contracture resolved with a standard physiotherapy treatment programme, including prolonged weight-bearing stretches and motor re-education, in 23 patients. Contracture persisted or worsened in 17 of 40 cases, all of whom exhibited dystonic muscle overactivity producing sustained equinovarus posturing. Ten of 17 cases required serial plaster casting (+/- injection of botulinum toxin type A) in order to achieve a functional range of ankle motion. Remediation of ankle contracture was not considered a priority in the remaining seven patients due to the severity of their overall disability.

CONCLUSION

The incidence of ankle contracture identified in this population was considerably less than previously reported. Reduced dorsiflexion range was remediated with standard physiotherapy treatment in over half of the cases. Additional treatment with serial casting +/- botulinum toxin type-A injection was required to correct persistent or worsening contracture in one quarter of cases. Dystonic extensor muscle overactivity was a major contributor to persistent or progressive ankle contracture.

Incidence of ankle contracture after moderate to severe acquired brain injury

OBJECTIVE

To examine an adult population undergoing rehabilitation after brain injury to determine the incidence of ankle contracture and factors contributing to the development of this deformity.

DESIGN

Descriptive study

SETTING

Specialist inpatient neurosurgical rehabilitation unit in Australia.

PARTICIPANTS

Patients (N=105) admitted with a new diagnosis of moderate to severe brain injury over a 12-month period.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Maximal ankle dorsiflexion range and the presence of abnormal muscle tone affecting the lower limb(s) were evaluated at weekly intervals. Ankle contracture was defined as maximal passive range of less than 0 degrees dorsiflexion with the knee in extension. Patients were grouped into 3 muscle tone categories: normal, predominantly spastic, or predominantly dystonic. Age, sex, mechanism and severity of brain injury, time to onset of ankle contracture, total length of hospital stay, and discharge mobility status data were also recorded.

RESULTS

Muscle tone was designated as normal in 68 (64.7%), as spastic in 14 (13.3%), and as dystonic in 23 (21.9%) patients. The incidence of ankle contracture was 16.2% (17/105 cases). Ankle deformity correlated closely with muscle tone category. Of 23 cases with dystonic muscle overactivity, 17 developed contracture at some point between 1 and 16 weeks after brain injury, although no subject with normal tone or spasticity developed the deformity. There was a weak association between the severity of brain injury and development of ankle contracture.

CONCLUSIONS

The incidence of ankle contracture was much lower than previously reported. Dystonic overactivity of the plantarflexor and invertor muscles is a major predisposing factor to ankle contracture.

Evaluation of serial casting to correct equinovarus deformity of the ankle after acquired brain injury in adults

OBJECTIVE

To determine the potential short-term benefit of serial plaster casting in the management of equinovarus deformity associated with acquired brain injury.

DESIGN

Prospective uncontrolled interventional trial.

SETTING

Inpatient rehabilitation facility in Australia.

PARTICIPANTS

Sixteen patients (19 limbs) with equinovarus deformity or deteriorating ankle range of motion associated with severe plantarflexor and invertor muscle overactivity underwent serial plaster casting over an 18-month period.

INTERVENTIONS

Below-knee plaster casts were reapplied weekly to increase joint range and muscle extensibility.

MAIN OUTCOME MEASURES

Precasting goniometric measures of maximal ankle dorsiflexion range (in knee extension and flexion) were compared with 4 subsequent test occasions (after initial cast, midpoint of casting, after final cast, 1 wk after removal). The amount and type of assistance required to perform a standardized wheelchair-to-bed transfer before and 3 months from commencement of casting were also compared.

RESULTS

Subjects who underwent the serial casting regimen had significantly improved ankle range (knee flexed mean, 18 degrees; knee extended mean, 16 degrees; P<.0001); 13 subjects reduced their need for transfer assistance (P<.0015).

CONCLUSION

Serial casting appears to be effective, at least in the short term, in reducing the equinovarus deformity that occurs after acquired brain injury. Greater ankle mobility was associated with improved transfer independence in the majority of subjects.