The Impact of Patellar Tendon Advancement on Knee Joint Moment and Muscle Forces in Patients with Cerebral Palsy

Background: Patellar tendon advancement (PTA) is performed for the treatment of crouch gait in patients with cerebral palsy (CP). In this study, we aimed to determine the influence of PTA in the context of single-event multilevel surgery (SEMLS) on knee joint moment and muscle forces through musculoskeletal modeling; Methods: Gait data of children with CP and crouch gait were retrospectively analyzed. Patients were included if they had a SEMLS with a PTA (PTA group, n = 18) and a SEMLS without a PTA (NoPTA group, n = 18). A musculoskeletal model was used to calculate the pre- and postoperative knee joint moments and muscle forces; Results: Knee extensor moment increased in the PTA group postoperatively (p = 0.016), but there was no statistically significant change in the NoPTA group (p > 0.05). The quadriceps muscle forces increased for the PTA group (p = 0.034), while there was no difference in the NoPTA group (p > 0.05). The hamstring muscle forces increased in the PTA group (p = 0.039), while there was no difference in the NoPTA group (p > 0.05); Conclusions: PTA was found to be an effective surgery for the treatment of crouch gait. It contributes to improving knee extensor moment, decreasing knee flexor moment, and enhancing the quadriceps and hamstring muscle forces postoperatively.

The association between gait analysis measures associated with crouch gait, functional health status and daily activity levels in cerebral palsy

PURPOSE: The aim of this study was to examine the relationship between gait analysis measures associated with crouch gait, functional health status and daily activity in ambulant cerebral palsy (CP). METHODS: Three-dimensional gait analysis was carried out on 35 ambulant participants with bilateral CP crouch gait (knee flexion at mid-stance (KFMS) ⩾ 190). KFMS, knee-flexion at initial contact, gait speed and step-lengths were extracted for analysis. Steps/day and sedentary time/day were assessed using an ActivPAL accelerometer. Functional health status was assessed using the five relevant domains of the Pediatric Outcomes Data Collection Instrument (PODCI) questionnaire. Associations between variables were assessed with correlation coefficients and multivariable linear regression. RESULTS: There were no significant correlations between KFMS and PODCI domains ρ=-0.008–0.110) or daily activity ρ=-0.297–0.237) variables. In contrast, multivariable analysis found that step-length was independently associated with the Sports and Physical Function (p= 0.030), Transfers and Basic Mobility (p= 0.041) and Global Function (< 0.001) domains of the PODCI assessment. Gait speed was independently associated with mean steps/day (p< 0.001). CONCLUSIONS: Step length and gait speed are more strongly associated with functional health status and daily activity than knee flexion during stance in children and adolescents with CP crouch gait.

Highly Selective Partial Neurectomy for Lower-Extremity Spasticity: 2-Dimensional Operative Video

Spasticity is a common debilitating condition after central nervous system injury. The principal therapies—sedating antispasticity medications and focal therapies (eg, botulinum toxin)—may not provide sufficient reduction in tone, have intolerable side effects, and lose efficacy over time. Selective neurectomy is a surgical option for durable reduction in tone.1-6 Although commonly performed internationally, neurectomies are used less often within the USA. We present the surgical case of a 23-yr-old woman with cerebral palsy and severe spastic diplegia. Medications, injections, and tendon surgeries had failed to relieve her spastic lower extremities. She presented with crouch gait, adductor scissoring, and bilateral equinovarus. She had previously benefitted significantly from bilateral hamstring and obturator neurectomies, with improvement in mobility. She desired tibial neurectomies for her bilateral equinovarus, which impacted her gait substantially. To reduce unwanted plantarflexion and internal rotation tone, selective neurectomies of the motor nerves to the medial and lateral gastrocnemius, soleus, and posterior tibialis muscles were performed. The surgical video details a technique for longitudinally opening the epineurium, separating small nerves into their individual fascicles, and subdividing submillimeter fascicles by approximately 50% to 60% of the fascicle cross-sectional area. She reported significant improvement in gait, her modified Ashworth score dropped from 3 to 0, and her motor power remained unchanged, which is equivalent or better than most published results.2,7 Neurectomies are a highly effective procedure for focal extremity spasticity. Additional clinical series or trials would help establish the appropriate indications and durability and quantify the risks and benefits. The patient consented to treatment and publication.