We report a prospective case-series study to evaluate the results of non-operative and operative treatment of symptomatic unilateral lumbar spondylolysis. Non-operative treatment results in healing in most patients with symptomatic unilateral spondylolysis. Surgery however is indicated when symptoms persist beyond a reasonable time affecting the quality of life in young patients particularly the athletic population.

We treated 41 patients [31 male, 10 female] with suspected unilateral lumbar spondylolysis. Thirty-one patients were actively involved in sports at various levels. Patients with a positive stress reaction on SPECT imaging underwent a strict protocol of activity restriction, bracing and physical therapy for 6 months. At the end of six months, patients who remained symptomatic underwent a Computed Tomography [CT] scan to confirm the persistence of a spondylolysis. Seven patients subsequently underwent a direct repair of the defect using the modified Buck's Technique. Baseline Oswestry disability index [ODI] and Short-Form-36 [SF-36] scores were compared to two year ODI and SF-36 scores for all patients.

In the non-operated group, the mean pre-treatment ODI was 36 [SD=10.5], improving to 6.2 [SD=8.2] at two years. In SF-36 scores, the physical component of health [PCS] improved from 30.7 [SD=3.2] to 53.5 [SD =6.5] [p<0.001], and the mean score for the mental component of health [MCS] improved from 39 [SD=4.1] to56.5 [SD=3.9] [p<0.001] at two years. 20/31 patients resumed their sporting career within 6 months of onset of treatment, a further 4/31 patients returned to sports within one year.

The seven patients who remained symptomatic at six months underwent a unilateral modified Buck's Repair. The most common level of repair was L5 (n=4). The mean pre-operative ODI was 39.4 (SD=3.6) improving to 4.4 (SD=4) at the latest follow-up. The mean score of PCS [SF-36] improved from 29.6 [SD=4.4] to 51.2 [SD=5.2] (SD=5.2) (p<0.001) and the mean score of MCS (SF-36) improved from 38.7 (SD=1.9) to 55.5 (SD=5.4) (p<0.001).

A specific protocol of conservative treatment for patients with a unilateral lumbar spondylolysis resulted in a high rate of success with 83% of patients avoiding surgery. If symptoms persist beyond a reasonable period (i.e. 6 months) and reverse gantry CT scan confirms a non-healing defect of the pars interarticularis one may consider a unilateral direct repair of the defect with good outcome ultimately.

Objective: To assess the radiological and back surface correction achieved following anterior USS in the treatment of thoracic adolescent idiopathic scoliosis (AIS).

Design: Prospective study of back surface correction, retrospective radiological review.

Subjects: 14 patients with thoracic AIS (age 11–18 yrs) were treated with anterior USS between 1995 and 2000. There are 12 females and 2 males, all with 2 year follow-up. 8 patients have complete surface data. Data from a further 6 patients will shortly be available as they reach 2 year follow-up.

Outcome measures: Cobb angle, apical vertebral rotation (AVR), apical vertebral translation (AVT), frontal plane imbalance, kyphosis and lordosis were measured from the radiographs. A Scoliometer was used to assess the maximal angle of trunk inclination (max ATI) in the thoracic region. All measurements were obtained before surgery and at 8 weeks, 1 year and 2 years after surgery. Complications were recorded.

Results: Significant initial corrections are observed for each of: Cobb angle (51%, p< 0.001), AVR (40%, p=0.003),AVT (64%,p< 0.001),maxATI (47%,p=0.001). There is no significant correction loss during the 2 year follow-up. Three patients had spinal imbalance (> 2cm) before surgery with one patient after surgery. The kyphosis significantly increased from 24° to 29° immediately after surgery with no significant change during follow-up. There was no change in lordosis. There were no neurological complications and no instrumentation failures were observed. In two cases the upper screw partially pulled out of T5 with some loss of correction.

Conclusions: Anterior scoliosis correction for thoracic AIS achieves good and stable radiological and particularly back surface corrections (max ATI – 47% compared with 22% correction after posterior surgery). Rigid anterior instrumentation has eliminated the 20% rod failure seen with Zielke. New techniques for preventing upper screw pull out will be discussed and new retractor systems allow smaller thoracotomies. There remains a small but significant increase in kyphosis which is less of a problem in the thoracic spine than at the thoracolumbar junction where anterior scoliosis correction is most commonly advocated.

Anterior instrumentation for thoracic AIS has advanced to a point where it can be widely adopted, particularly if the patient expresses concerns regarding the rib hump or is hypokyphotic.