Weinstein Lovell and Winters Pediatric Orthopaedics 7e

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CHAPTER 30  |  The Child with a Limb Deficiency

lower leg and dividing in the sole of the foot, have also been found (137).

Natural History.  There are no reports on the natural his- tory of tibial deficiency. In bilateral cases of type Ia deficiency, ambulation is not observed. The authors have observed several patients with bilateral types 2 and 3 tibial hemimelia who pre- sented for treatment between the ages of 5 and 8 years. These children were ambulatory but had complaints of pain due to foot deformity or proximal fibular prominence. Treatment Recommendations Nonsurgical Treatment.  Nonsurgical treatment is only indi- cated in the patient with bilateral tibial deficiency with active knee extension and acceptable foot position. Any other patient with tibial deficiency stands to gain much by the various types of surgical treatment. Surgical Treatment.  The treatment of Jones type Ia tibial deficiency without active knee extension is knee disarticula- tion and prosthetic fitting. However, there are several reports in the literature of attempts to centralize the fibula between the femoral condyles, which are discussed below. Originally described by 1905 by Myers (128) and subsequently by Sulamaa and Ryoppy in 1963 (138), the Brown procedure, as it is commonly known in the United States, is the centraliza- tion of the fibula under the femur (139, 140). It was Brown’s recommendation that fibular centralization be done only with active knee extension, which is rarely seen in the case of a completely absent tibia. Most reports on the Brown proce- dure, however, include significant numbers of patients who did not have well-documented active knee extension before surgery. Some reports also erroneously include patients who actually had transfer of the fibula to a proximal tibial remnant rather than complete transfer of the fibula under the femo- ral condyles. The surgery has now been evaluated in several clinical trials (132, 133, 141–144). Most of those reporting on the procedure recommend against it, preferring the early function obtained with knee disarticulation (132, 133, 142). Loder (145) examined 87 cases from the literature using the minimal requirements for a good result, as suggested by Jayakumar and Eilert (144), of acceptable gait, active knee motion of 10 to 80 degrees of flexion, varus/valgus instabil- ity <5 degrees, and no flexion contracture. He found that 53 of the 55 cases of Jones type Ia deficiency treated by Brown’s procedure had a poor result because of flexion contracture. Many other authors have reported similar results and empha- size the need for strong active knee extension for a good result (132, 141–144). Simmons et al. were satisfied with the results from their evaluation of Brown’s procedure (142). Their satisfaction was based more on the patients’ feelings than objective assessment. Wada et al. (147) found that patients could weight bear in the home without assistive devices after the procedure but had poor function outside of the home and required a knee orthosis to ambulate. Like others, they

FIGURE 30-23.  Clinical photograph of the lower extremity of a patient with tibial deficiency. Note the equinovarus foot position and shortening of the lower leg as compared to the thigh segment.

Other Imaging Studies.  Rarely, there is difficulty deter- mining the clinical presence of an unossified proximal tibia in the infant in Jones 1b tibial deficiency. Some authors have recommended obtaining an ultrasound (135) or MRI to detect its presence. MRI can be useful in this situation because it can identify the rare patient with active knee extension and no tibial remnant, who is treated differently than the patient with active knee extension and a tibial remnant. Pathoanatomy.  Pathoanatomy has been determined from specimens at the time of knee disarticulation. Common find- ings include an anomalous fibrotic band attached via inter- osseus membrane to the fibula, the presence of unidentified muscle attached to the tip of the lateral malleolus, and the duplication of anterior compartment muscles. Abnormal cru- ciate ligament, collateral ligament, and menisci are often seen. The patella is always abnormal and often absent, with the absence of the patellar ligament. Popliteal artery division has been described as being more distal than normal, with bifur- cation at the ­midfibular level (129, 136). Lack of a normal- appearing tibial nerve, with a lateral nerve coursing down the