[Lengthening of proximal femoral focal deficiency using a hybrid fixation with inclusion of the knee joint]

Lengthening With External Fixation Is Effective in Congenital Femoral Deficiency

BACKGROUND

Treatment of congenital femoral deficiency is a complex, multistage protocol and a variety of strategies have been devised to address joint instability, limb length inequality, and deformities. Despite being an important part of the algorithmic approach to the overall treatment of patients with congenital femoral deficiency, a reproducible, safe, and functional treatment for femoral length discrepancy in patients with mild and moderate congenital femoral deficiency has not been reported.

QUESTIONS/PURPOSES

(1) Does femoral lengthening by means of distraction osteogenesis, using a monolateral external fixator, result in effective lengthening without loss of hip or knee range of motion? (2) Does femoral lengthening cause an inhibition of femoral growth in patients with congenital femoral deficiency? (3) Do patients/families report satisfactory functional and emotional outcomes after undergoing femoral lengthening? (4) What proportion of patients develops complications after femoral lengthening with this technique?

METHODS

Between 2005 and 2009, we evaluated 38 patients for femoral length discrepancy secondary to unilateral congenital femoral deficiency. Thirty-two patients completed treatment with distraction osteogenesis using a monolateral external fixator; general indications for this approach were congenital femoral deficiency Paley Types 1a, 1b, or 2a that had not previously undergone lengthening and had stable hip and knee joints. Of the 32 patients that completed treatment, 30 (94%) were available at a minimum of 2 years (mean, 3 years; range, 2-4.5 years) and were evaluated in this retrospective study. Preoperative and postoperative radiographic analysis, physiotherapy data, patient-based outcomes scores, and complications were reviewed for all eligible patients. Growth inhibition was measured using serial radiographs over the 2-year followup with the unaffected limb considered the norm. Functional and emotional outcomes were reported by adolescent patients or parents of younger children using the Pediatric Orthopaedic Society of North America Pediatric Outcomes Data Collection Instruments (PODCI), a validated patient-based outcomes measure.

RESULTS

The mean distal femoral lengthening was 6 cm (SD ± 2 cm; range, 1.6-9 cm), for a mean percent of femoral length discrepancy correction of 112% (SD ± 55%; range, 15%-215%). Comparison of patient preoperative with postoperative mean hip and knee flexion and extension showed no difference with the numbers available (hip flexion: p = 0.219, mean difference of -5, 95% confidence interval [CI], 10, SD = 20; hip extension: p = 0.423, mean difference of -1, 95% CI, 2, SD = 5; knee flexion: mean difference of -7°, SD ± 29°, CI, 15, p = 0.467; knee extension: mean difference of -1°, SD ± 9°, CI, 4, p = 0.757). A comparison of the mean preoperative inhibition of 41% (range, -38% to 300%; SD ± 72; 95% CI, 29%) with the mean postoperative inhibition of 16% (range, -242% to 100%; SD ± 61%; 95% CI, 25%) for a mean postoperative stimulation of 25% (p = 0.055, SD ± 90%; 95% CI, 36%). In all six PODCI categories surveyed, patients had favorable standardized and normative scores, but patients who underwent femoral lengthening greater than 6 cm had both lower global functioning scores (90, SD ± 10 versus 96, SD ± 3, p = 0.043) and worse pain/comfort scores (79, SD ± 25 versus 96, SD ± 7, p = 0.029), and patients who had mean percent femoral lengthening greater than 25% of initial femur length had worse pain/comfort scores (79, SD ± 23 versus 97, SD ± 4, p = 0.012) with similar global functioning scores (90, SD ± 9 versus 96, SD ± 3, p = 0.058). The total number of postsurgical complications was 30 in 60 planned surgical procedures (50%).

CONCLUSIONS

Our study results support the use of the described surgical technique for femoral lengthening in treating patients with congenital femoral deficiency. Additional studies are needed both to follow long-term patient-reported outcome measures, especially after a second or third lengthening, and to determine the effect of serial lengthening on the stimulation or inhibition of growth and rate of complications.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

[Esthetic and functional improvement in proximal femoral focal deficiency with lacking hip joint by rotation plasty Winkelmann type BIII]

BACKGROUND

Proximal femoral focal deficiency (PFFD) types II and III (Pappas) have no femoral or only abortive femoral head development. Winkelmann published a case of one patient treated with a modification of rotation plasty by creating a new articulation after 180° rotation of the lower leg and insertion of the lateral tibial plateau into the deficient acetabulum. This article reports on three consecutive patients treated with this technique to validate this procedure and to consider this operation in selected patients.

PATIENTS AND METHODS

At the time of rotation plasty the patients (2 boys and 1 girl) were aged between 5 and 10 years. The observation period is between 5 and 9 years after surgery. All patients used an orthoprosthesis with full contact in the foot region and a shaft connecting the thigh. A hip basket and any additional walking support were not necessary (e.g. canes). They were all highly satisfied and would choose the same treatment again.

CONCLUSION

Rotation plasty is a technically highly demanding procedure, especially in situations such as PFFD where the anatomy is distorted and structures such as blood vessels and nerves are too short. However, it is an option to improve the orthoprosthetic fitting functionally and esthetically.