Proximal humerus deformity, in a four-limb amputee following meningococcal septicaemia

Abstract

We present a challenging case of proximal humerus varus deformity in a four-limb amputee, caused by growth arrest from meningococcal septicaemia. The deformity resulted in a loss of function for our patient with inhibition of activities of daily living, requiring corrective osteotomy to help improve the range of motion of the shoulder. We describe in detail the management of our patient, highlight the importance of the orthopaedic manifestations of meningococcal septicaemia, and demonstrate the importance of monitoring potential deformities from growth arrest in these patients.

Background

Meningococcal septicaemia is a leading cause of morbidity and mortality in childhood. Despite vaccinations the serogroup B variant continues to predominate in the UK, causing a multitude of significant late complications.¹ The orthopaedic manifestations result from growth arrest leading to complex deformities. The growth arrest can either be central, peripheral or both. Central arrest leads to limb length discrepancies requiring lengthening procedures and peripheral arrest leads to angular deformities requiring corrective osteotomies with or without ablation of the damaged physis.

Damage to the growth plate can present years after the initial acute illness. The most common sites affected are the lower limbs, predominantly the knee and ankle and usually involves multiple growth plates. Reportage of growth arrests in the upper limb are scarce from the literature, there is only one case involving the distal humerus, and two cases involving the proximal and distal, radius and ulna but these did not have an angular deformity.² We describe a challenging case of proximal humerus deformity consequent to a growth arrest caused by meningococcal septicaemia, which required corrective osteotomy of the proximal humerus for improvement in shoulder function.

Case presentation

A 14-year-old girl with a history of meningococcal septicaemia resulting in four-limb amputation at the age of 7, presented to our shoulder unit from her general practitioner and physiotherapist, with reduced range of movement in her left shoulder consequently affecting her activities of daily living. She was unable to reach overhead shelves, including her wardrobe. Personal care was difficult specifically brushing her hair and dressing. She had pain when lying on her side at night. She was unable to abduct (figure 1) or forward flex (figure 2) past shoulder height and had a sensation of a mechanical block when attempting active elevation and abduction.

Figure 1.

Reduced shoulder abduction.

Figure 2.

Reduced shoulder forward flexion.

She used a prosthetic strap to hold a pen and cutlery, and artificial blades for both lower limbs. The functional deficit due to the restriction in elevation of the left arm above shoulder height was magnified because of the four-limb amputation. It was the patient’s view that even a small improvement in the left arm elevation would afford her big gains in her functional status.

Investigations

Plain radiographs of the left shoulder demonstrated a proximal humerus varus deformity of the head of the humerus with a prominent greater tuberosity (figure 3). A contralateral X-ray of right shoulder was obtained for comparison, which demonstrated valgus deformity. The right side was asymptomatic with no pain and a full range of movement. CT scan indicated that the proximal humerus physis had fused (figure 4).

Figure 3.

Anteroposterior radiograph of the left shoulder proximal humerus varus deformity, with prominent tuberosity.

Figure 4.

CT scan demonstrating fusion of the proximal humerus physis and varus deformity.

Differential diagnosis

Differential diagnosis included varus malunion of the proximal shoulder following possible fracture, bony block and physeal growth arrest with compensatory growth of the greater tuberosity physis. CT reconstruction and the rotational profile were obtained and combined consultation undertaken with the paediatric orthopaedic team.

Treatment

Initially, an examination under image intensifier was performed, which demonstrated no evidence of shoulder instability. There was evidence of direct mechanical impingement of the humeral greater tuberosity against the lateral acromion producing a block to movement beyond 90° of lateral abduction and elevation, associated with some discomfort. Rotational movement was without restriction (figure 5).

Figure 5.

Examination under anaesthesia, demonstrating mechanical impingement of tuberosity against acromion.

Left shoulder proximal humerus corrective osteotomy for varus was planned as per the technique described by Gill and Waters (figure 6).³ In the beach chair position a deltopectoral approach to the shoulder is performed. The original technique describes the use of two Kirschner wires (K-wires) introduced to the lateral cortex of the humeral shaft at the site of deltoid insertion, directed proximally to the humeral head perpendicular to the planned osteotomy site. Following osteotomy, the K-wires are then advanced and tension band fixation is prepared using No1 Ethibond suture in a figure of eight fashion between the insertion of the rotator cuff at the greater tuberosity and the K-wires at the humeral shaft. The osteotomy is made under direct vision; an oblique closing wedge osteotomy is performed. Osteotomies are made to converge at the radiographic notch corresponding to the point of medial physeal arrest. To avoid iatrogenic injury to the ascending branch of the anterior circumflex humeral artery and thus minimise the risk of humeral head osteonecrosis, the osteotomy is created laterally and care taken to preserve the far medial humeral cortex. The medial humeral cortex and periosteum are left intact allowing it to serve as a hinge during closure of the osteotomy.

Figure 6.

Planning the proximal humerus osteotomy according to the technique described by Gill and Waters.³

For our case, a 15 mm wedge of bone from the proximal humeral metaphysis was removed just lateral to the rotator cuff insertion using K-wires and intraoperative imaging as a guide to the osteotomy (figures 7 and 8). The osteotomy was compressed and fixed using a DePuy Synthes LCP Paediatric hip locking plate (figure 9). A 130° locking plate was inserted at 100° for 30° correction of valgus. Subsequent removal of the locking plate was performed once union was established 8 months later.

Figure 7.

Use of Kirschner wires to guide osteotomy.

Figure 8.

15 mm wedge of bone removed from proximal humerus metaphysis.

Figure 9.

Intraoperative fluoroscopy demonstrating fixation using paediatric hip locking plate.

Outcome and follow-up

The patient progressed well postoperatively and worked with physiotherapists. Gains in overhead range of motion were obvious in the first 8 weeks. The mechanical block to movement was absent. One-year follow-up from proximal humerus corrective osteotomy, abduction and elevation was 10° short of the right shoulder, which passively goes further with no shoulder pain or blocking (figures 10 and 11). The patient was happy with the functional gain achieved by the improved movement.

Figure 10.

Post-operative shoulder abduction.

Figure 11.

Post-operative shoulder forward flexion.

Discussion

Kohler⁴ described the radiographic criteria of proximal humerus varus, which included a neck shaft angle of less than 140°, a greater tuberosity elevated above the superior margin of the humeral neck as seen on the anteroposterior (AP) radiograph, and a reduced distance between the articular surface of the humeral head and lateral cortex of the humerus. The radiographic ‘notch’ in the region of the medial physis corresponds to the region of physeal arrest resulting in impingement of the greater tuberosity on the acromion leading to pain and limited shoulder function with regard to shoulder abduction and forward flexion. Gill and Waters³ first described the technique for valgus closing wedge proximal humerus osteotomy with tension band fixation and Ugwonali et al⁵ demonstrated the outcome in pain and improvement of shoulder movement in a case series of six patients treated with the aforementioned method. The average forward flexion and abduction presurgery was 76° and 63°, respectively, and the radiographic neck shaft angle was 95°. The average immediate postsurgery valgus correction was 31°, which resulted in an average neck shaft angle of 130°. An average improvement post-surgery of forward flexion and abduction was noted of 61° and 57°, respectively, all results being statistically significant.

The long-term orthopaedic manifestations of meningococcal septicaemia present a challenge to the orthopaedic surgeon. Buysse et al⁶ demonstrated a significant correlation between the severity of disease and major skin and orthopaedic sequelae. Bache and Torode⁷ found invariably amputation was associated with proximal physeal growth arrest and described 41 cases of arrest in 16 patients. Belthur et al⁸ similarly showed 23 patients having 49 growth arrests.

The pathogenesis of the growth plate arrests results from two possible theories. Neisseria meningitidis endotoxin induces an ischaemic insult, which causes a diffuse vasculitis and disseminated intravascular coagulation. This then leads to an acute vascular occlusive process, which results in bone ischaemia. This is followed by a discrete inflammatory response contributing to further ischaemia.^{6 9–11} Another theory states that burn scars or areas of necrotic skin could act as a tether producing a type 6 growth plate injury involving the periphery of the plate and particularly the ring of Ranvier.¹² However, the areas of skin necrosis may not necessarily lie over the growth plate and hence this theory is less likely.

In order to address the deformities presented, a complete clinical and radiological examination is necessary including the use of radiographs and CT scans to identify and characterise multiplanar deformities, and growth plates affected. In the lower limbs estimations of final limb length discrepancy can be made using the arithmetic method with the distal femur contributing 9 mm of growth a year, the proximal tibia 6 mm a year and distal tibia 5 mm a year.^{13 14} With serial measurements, the estimate is more accurate by using the multiplier method of Paley et al.¹⁵

However, as upper limb deformity is rare, there is currently very little guidance on the management of these patients.

Angular correction and lengthening with a percutaneous epiphysiodesis had no recurrence of angular deformity and the role of epiphysiodesis in preventing recurrent deformity has been highlighted by Nectoux et al.^{16 17}

Previous literature includes cases where surgical management has been advocated in the form of limb lengthening and corrective osteotomies to improve symptoms including revision of amputations, which were initially performed as life-saving procedures during the acute episode of illness.

In young children, there is a possibility of stopping the deformity from getting worse by epiphysiodesis (but difficult to know when a physeal bar has formed in cases of meningitis). It is, however, preferable to do an osteotomy and also obliterate the growth plate completely to prevent recurrent deformity once a deformity or growth arrest has been detected during surveillance of the child.

There is little guidance for orthopaedic surgeons managing these complex conditions. Furthermore, the literature supports the use of screening to monitor physeal growth arrest for patients undergoing amputations for meningococcal septicaemia. We feel obliged to highlight the importance of follow-up in such cases by presenting our case.¹⁸

Learning points.

• Patients with amputations following meningococcal septicaemia should be referred directly to the paediatric orthopaedic service for monitoring of growth deformities until skeletal maturity.

• Parents of children with meningococcal septicaemia should be advised to monitor for deformities and advised to seek general practitioner referral to the paediatric orthopaedic service.

• A complete clinical and radiological examination should be performed to establish the growth plates involved.