Management of Verterbral Compression Fractures (VCFs) in Multiple Myeloma (MM) Patients with Balloon Kyphoplasty

MM is the second common haematological malignancy representing 1% of all cancers. It is the most frequent cancer that involves the bone. MM patients develop painful VCFs that cause substantial morbidity, compromise quality of life and increased healthcare costs. Management of MM spinal disease (MMSD) remains challenging. BKP has purported benefits of relieving pain and restoring function but the indications, timing, efficacy, safety and the role of BKP in the MMSD treatment of are yet to be defined.

The aim of this study was to retrospectively analyse the outcome of the use of BKP for MRI confirmed VCFs in MM patients referred at the MM Spinal Unit at RNOH between January 2008 and June 2014.

All patients were on systemic myeloma treatment, bisphosphonates, pain relief and based on the VCF level were fitted with brace. Indications for BKP were persistent severe pain, spinal instability, neurological symptoms, fracture level and associated high risk for severe kyphosis. All patients had prophylactic antibiotic cover for the BKP and their chemotherapy withheld for 1 week.

The total of 274 MM patients presented with VCFs. The mean age was 64±12 years old and 144 (53%) were male. 145 operations perfomed. 127(47%) patients were treated with at least one operation, 107(86%) patients had only one operation, 16(13%) patients had two operations and 2 (2%) patients had three operations. The median time from diagnosis to BKP operation was 23(9-61) months, from diagnosis to last follow-up was 104(46-166) months and from BKP to last follow up was 23(9-61) months.

BKP was performed in 127 MM pts of the total of 274 pts presented with VCFs. These patients had graded Visual Analog Score (VAS) for pain ≥6 although on high doses opioid pain relief. The mobility was restricted in 23% of the patients (ECOG ≥3). The median age at the time of the BKP was 65 (39-92) years and the MM subtype was IgG (35%), IgA (18%), light chain (14%), non-secretory (4%), IgD in 2%. 46% of the patients underwent BKP at presentation within a median time from diagnosis to BKP of 23(9-61) months. The median follow up from operation was 23(9-61) ranging from 2 months to 209 months.

A total of 356 painful VCFs levels were treated with BKP in 145 operations on 127 patients. The non- BKP conservatively managed VCFs had adequate pain control and no risk for spinal instability. In addition a percentage of these patients had bone development and conferred their own stability. A single vertebral level was treated in 40(32%), with two levels treated simultaneously in 32(26%) patients and three or more levels in 49(39%) patients in the overall population with VCFs. Of the 379 VCFs identified by MRI, the most common fractured vertebral level was at T12 level 47(12%) followed by L2 37(9.6%) followed by T11 and L1 36(9.4%) vertebral bodies. 109 of the 379 VCFs levels were affecting the posterior wall. Median Spinal Instability Neoplastic Score (SINS) was 11 (10-13). VAS was improved from ≥6 to 1.1±2.0 following the BKP. 69 % of the patients had rapid pain relief, became independent of pain relief and their mobility and functionality were markedly improved within a median time of 6 weeks (4 days to 3.5 months). For 61% of the patients mobility improved gradually in view of additional problems with steroid induced myopathy. In addition improvement of functionality was shown. Asymptomatic cement leak was found in 41 levels but no other BKP related toxicity was reported.

Nine pts with VCFs presented with MRI findings of cauda equine (6 with associated neurology). In 14 pts the MRI was consistent with spinal cord compression (9 with abnormal neurology). Nerve root compression was found in 6 pts (all symptomatic). 16 patients required radiotherapy in addition to the acute MMSD management. Only 3 patients underwent urgent major surgical intervention for spinal instability and fixation. Neurology completely resolved in all but one patient. 14 vertebral levels were managed with BKP for deformity prophylaxis.The incidence of major surgical stabilisation procedures was very low and this was successfully replaced by BKP.

In conclusion these data suggest that BKP is a safe procedure for the management of MMSD/VCFs provides rapid and sustained pain relief, could prevent deformity and maintain functional improvement and QOL.