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Calf lengthening may improve knee recurvatum in specific children with spastic diplegic cerebral palsy
Jeremy Bauer1, K Patrick Do1, Jing Feng1
1Shriners Hospitals for Children, Portland, Oregon, USA.
Insights
Calf lengthening surgery can improve knee hyperextension in children with spastic diplegic cerebral palsy (CP) who have calf contractures. Early intervention may lead to better outcomes for managing this challenging condition.
Area of Science:
- Orthopedics
- Pediatric Rehabilitation
- Movement Science
Background:
- Knee hyperextension in stance is a challenging condition in children with spastic diplegic cerebral palsy (CP).
- Calf contracture or spasticity often contributes to passive knee hyperextension during the stance phase.
- Surgical intervention targeting calf contractures is a potential treatment approach.
Purpose of the Study:
- To investigate the efficacy of calf lengthening surgery in reducing knee hyperextension in children with spastic diplegic cerebral palsy (CP).
- To compare outcomes between early and late recurvatum groups following calf lengthening surgery.
Main Methods:
- Retrospective review of children diagnosed with CP (Gross Motor Function Classification System I-III) over 23 years.
- Inclusion criteria: passive knee hyperextension and undergoing calf lengthening surgery.
- Patients divided into early recurvatum (ER, n=20) and late recurvatum (LR, n=14) groups.
Main Results:
- Calf lengthening improved static dorsiflexion in both ER (9.3°) and LR (9.6°) groups.
- Kinematic analysis showed significant improvement in knee hyperextension by 11° in the ER group (p < 0.001).
- The LR group did not demonstrate significant changes in stance phase knee position.
Conclusions:
- Calf lengthening surgery can benefit children with passive knee hyperextension due to calf contracture, particularly those exhibiting hyperextension early in stance.
- The findings suggest that early surgical intervention may be more effective in correcting knee hyperextension.
- Level of Evidence: III.
Purpose:
Knee hyperextension in stance is a difficult condition to treat in children with spastic diplegic cerebral palsy (CP). In children with passive knee hyperextension, the presence of contracture or spasticity of the calf leads to knee hyperextension in stance phase. We hypothesize surgical treatment of the contracture of the calf will lead to less knee hyperextension.
Methods:
We performed a retrospective review of children who were evaluated in our movement laboratory over 23 years with a diagnosis of CP Gross Motor Function Classification System I, II or III. We selected children who had passive knee hyperextension on exam and who underwent calf lengthening surgery. Children were divided into two groups: early recurvatum (ER) (n = 20) and late recurvatum (LR) (n = 14).
Results:
There was no difference in the preoperative passive knee extension among the groups or the surgeries performed. For children who had passive knee hyperextension, calf lengthening improved static dorsiflexion with knee flexion on clinical exam by 9.3° in the ER group, 9.6° in the LR group as well as dorsiflexion with knee extension on clinical exam by 9.5° in the ER group and 6.4° in the LR group. The kinematic data showed that the ER group improved their knee hyperextension by 11° (p < 0.001), whereas the LR group did not significantly change their stance phase knee position.
Conclusion:
Children with passive knee hyperextension who have a calf contracture and walk in knee hyperextension in the first half of stance phase may improve after calf lengthening.Level of Evidence: III.
