Quantification of Increase in Three-dimensional Spine Flexibility Following Sequential Ponte Osteotomies in a Cadaveric Model.

BACKGROUND: Posterior-only procedures are becoming more popular for treatment of rigid adolescent idiopathic scoliosis, but little is known about the quantitative correction potential for Ponte osteotomies. The objective of this study was to quantify and compare the range of motion of intact multilevel thoracic spine segments with the same segments after each of 3 sequential Ponte osteotomies. METHODS: We tested 5 human cadaveric thoracic spine segments, spanning T-T6, or T7-T12, in an 8-degree-of-freedom servo-hydraulic load frame, monitoring motion of each vertebra with an optical motion tracker. We measured range of motion while we applied cyclic, pure moment loading to produce flexion-extension, lateral bending, and axial rotation at a rate of 0.5°/second, to a maximum of ± 6 Nm. Each specimen was tested intact and after each of 3 sequential Ponte osteotomies. RESULTS: Total range of motion for the segments (either T2-T5 or T8-T11) increased by as much as 1.6° in flexion, 1.5° in extension, 0.5° in lateral bending, and 2.8° in axial rotation with each osteotomy. Because of the variation in initial specimen stiffness, we normalized motions to the intact values. In flexion, average range of motion increased after each osteotomy compared with intact, by 33%, 56%, and 69%. In extension, slightly smaller increases were seen, increasing by as much as 56% after the third osteotomy. In lateral bending, Ponte osteotomies had little effect on range of motion. In axial rotation, range of motion increased by 16%, 29%, and 65% after 3 osteotomies. CONCLUSIONS: Sequential Ponte osteotomies increased range of motion in flexion, extension, and axial rotation, but not in lateral bending. These results suggest that the Ponte osteotomy may be appropriate when using derotational correction maneuvers, or to improve apical lordosis at the apex of curvature during posterior spinal fusion procedures. Although these techniques are effective in gaining correction for kyphotic deformities and rigid curvatures, they add time and blood loss to the procedure.

Triple arthrodesis with lateral column lengthening for the treatment of planovalgus deformity.

BACKGROUND: The rigid planovalgus foot has historically been difficult to correct and maintain in a corrected position with triple arthrodesis (TA). The lateral column lengthening (LCL) is a procedure that corrects the position of the planovalgus foot. Combining the TA with LCL at the calcaneocuboid joint may improve ultimate position after fusion for patients with rigid planovalgus foot deformities. METHODS: A retrospective review of all patients who underwent TA with LCL through the calcaneocuboid joint for rigid planovalgus foot deformity was performed. Preoperative and postoperative radiographs were compared for foot alignment by measuring the talo-first metatarsal angle in the anterior-posterior and lateral planes, calcaneal pitch, talo-horizontal angle, metatarsal stacking angle, and medial/lateral column ratio. Clinical outcomes were evaluated for correlation with preoperative and postoperative deformity and surgical indications. RESULTS: were evaluated using radiographic and clinic outcome measures developed for TA and LCL. RESULTS: : Twenty-nine surgeries were identified with solid fusions occurring in 27 patients by 12 weeks postoperatively. Two patients with cerebral palsy had persistent hindfoot valgus. At an average follow-up of 32 months after surgical intervention, correction of the talo-first metatarsal angle in the AP and lateral planes, calcaneal pitch, and talo-horizontal angles were statistically significant. There were 25 good clinical results with minimal or no pain with activity (86.2%) and 4 poor or fair results with moderate or severe pain (13.8%). There were 26 radiographic successes (89.7%) and 3 radiographic failures (10.3%). Cerebral palsy was associated with a higher rate of radiographic failures (P=0.01). There were 15 total complications in 11 feet (37.9%). These included 4 related to hardware, 3 involving neurological symptoms, 2 related to soft tissues, development of a symptomatic bony prominence in 2 patients, 1 forefoot deformity, 2 nonunions, and 1 case of Achilles tendonitis. CONCLUSION: Good correction can be obtained and maintained with LCL and TA for rigid planovalgus foot deformity. The procedure is associated with good short-term clinical and radiographic outcomes and improves the position of the foot with diminished risk of recurrent or continued deformity as compared with historical controls. LEVEL OF EVIDENCE: Level IV (case series).

Scapular osteochondromas treated with surgical excision.

A retrospective review was performed of all osteochondroma excisions at our institution from 1994 to 2007. Postoperative functional assessment was completed with use of the Disabilities of the Arm, Shoulder and Hand (DASH) survey and a self-report questionnaire. Eight osteochondromas were excised at a mean patient age of 21.63 years. Presenting reports included pain, mass, pseudowinging, and snapping of the scapula. Physical examination identified pseudowinging, palpable mass, and pain with shoulder motion. The lesions arose from the ventral surface of the scapula in 5 patients, the dorsal surface in 2, and the inferior acromion in 1. The resected specimen averaged 10.8cm(3). A reactive bursa was found and resected in 4 patients. At mean of 4.17 years postresection, no signs of recurrence were found in 7 patients (88%). The single patient with a recurrence had undergone 2 additional surgical procedures. Six patients (75%) reported no/mild pain with routine and strenuous activities. One patient reported moderate and 1 patient reported moderate/severe pain with routine and strenuous activities. Four patients reported post-resection function as excellent, 2 as good, 1 as average/good, and 1 as average/poor. Six patients (75%) reported feeling very satisfied with the results, 1 reported feeling satisfied, and 1 reported feeling unsatisfied. The average DASH score was 11.7 (range, 0.00-46.67). No winging or pseudowinging was identified in those available for examination, and no difference was identified in range of motion comparing the operative to the nonoperative upper extremity. Near normal functional outcomes can be expected following excision of scapular osteochondromas.