Purpose: In evaluating injury severity of acute medial collateral ligament (MCL) injuries, the current standard is to perform a history and physical examination and static MRI of the injured joint. With recent advances in dynamic MR imaging technology, we hypothesized that concurrent physical examination and dynamic MRI of the knee joint in patients with acute MCL injuries is feasible and would provide new insight into the injured joint kinematics while correlating to clinical and diagnostic imaging criteria for injury severity.

Method: 10 patients (5 male, 5 female) with isolated, unilateral, acute MCL injuries were prospectively enrolled in the study. An orthopedic surgeon performed initial physical examination and clinical grading. Dynamic MRI with concurrent physical examination was performed in a 1.5T wide-bore magnet and compared to the uninjured knee as a control. The dynamic MR imaging data was compared with morphologic MCL changes on static MRI, with dynamic examination of the contralateral knee and with the clinical grading of MCL injury. The width of the medial joint space and the opening angle between the femur and tibia were measured.

Results: Clinically, one patient had grade 1 and nine had grade 2 injuries. Using morphologic MRI criteria there were nine grade 2 and one grade 3 injuries. Mean and median medial opening angles of all affected knees was 2.8/2.5 mm and 2.8/2.6°, respectively, as compared to 1.8/1.8 mm and 2.2/2.1° in the normal side. Measurements of medial joint-space opening showed little quantitative difference between grade 1, 2 and 3 injuries. Interobserver agreement (intraclass correlation coefficients) varied from 0.9 to 0.93.

Conclusion: Dynamic MR imaging with concurrent physical examination is feasible and correlates to clinical and morphologic grading of severity. Our study suggests that traditional clinical grading systems of MCL injuries overestimate medial joint space opening.

The objective of this study is to determine if surgical lengthening of the hamstrings and gastrocnemius/Achilles complex, affect muscle tone in patients with cerebral palsy. The question is if the dynamic component of muscle length changes after orthopedic surgery. A retrospective study was performed on ambulatory children with cerebral palsy who underwent either hamstring lengthening or gastrocnemius/Achilles tendon lengthening. A total of 135 consecutive patients with an average age of 13 years were included in the study. A single random side was selected for children with bilateral surgery and the affected limp was analyzed for those undergoing unilateral surgery. The popliteal angle was performed with a quick and slow stretch, as well as, the ankle dorsiflexion, and measured with a goniometer.

The difference between initial grab with fast stretch, and end of range (EOR) with slow stretch was used as a measure of spasticity. The Bohanon modification of the Ashworth score was also assessed. 18° popliteal angle improvement in end of range and 32° improvement in quick stretch in the hamstrings group were notice postoperatively, with change in slow stretch, quick stretch and Δml (comparison between quick and slow stretch) being significant at p< .0001. In the triceps surae group, 14° ankle dorsiflexion improvement in end of range, and 18° improvement in quick stretch were noticed postoperatively, with change in slow stretch, quick stretch and Δml at p< .0001, p< .0001, and p< .0180 respectively. Asworth scale was reduced by at least one grade in 89% of subjects in the hamstring group and 78% of subjects in the triceps surae group of the children with preoperative Asworth 3 and above. We concluded that significant decreases in spasticity were observed following tendon lengthening in children with cerebral palsy and that the orthopedic surgery can affect both static and dynamic components of muscle tightness in these children.

The iliopsoas is considered a major deforming force causing hip flexion deformity in children with cerebral palsy. Although iliopsoas release at the lesser trochanter is thought by many clinicians to cause excessive hip flexor weakness, we believe that it does not produce iatrogenic hip flexion weakness. We were unable to find a study in the literature that objectively studied this issue. Included in the study were 25 patients, all ambulators with cerebral palsy (any type). They underwent iliopsoas release at the lesser trochanter and multiple surgeries (soft tissue with or without bony procedures). Mean age at surgery was 11.4 years.

Motion analysis was performed to all patients prior to surgery and one year post-op. Hip and knee range of motion was improved with out significant decrease in hip flexion power. Maximum hip extension improved, no change in maximum and total flexion power generation was found. As expected, hip range of motion was improved significantly. We proved that when releasing the iliopsoas at the lesser trochanter, the change in power generation is statistically insignificant, as shown by maximum and total hip power generation in swing phase.