Surgical Fixation of Metacarpal Shaft Fractures Using Absorbable Implants: An Update of the Literature

Background: Despite the proven efficacy and advantages of absorbable implants, their use for metacarpal shaft fixation has been limited. This is likely due to the high reported complication rates in early studies with polyglycolic acid (PGA) implants, notably high rates of noninfectious inflammatory reaction (5-25%), occurring up to 30 weeks after fixation. The objective of this study was to assess the clinical outcomes of newer absorbable plates and screws composed of polylactic acid (PLA) in the treatment of metacarpal shaft fractures. We hypothesize that our findings will support the use of PLA implants for metacarpal fracture fixation.

Methods: The authors performed a systematic search of the PubMed, Ovid MEDLINE and EMBASE databases dating from 1946 to 2017. Primary outcome measures were the development of non-infectious inflammatory reaction and implant failure.

Results: A total of 42 metacarpal shaft fractures in 35 patients were included in this study. The average follow-up time was 20.4 months (n=24; range: 3.6-61 months). Only 1 case (2.4%) of non-infectious inflammatory reaction was reported with polylactic acid (PLA) plates and PLA/PGA compounds. Non-infectious inflammatory reaction was observed in 4 out of the 9 patients (44.4%) with a trimethylene carbonate/PLA compound. Symptoms appeared after an average time of 15.8 months (range 12-19 months) post-fixation. Painless prolonged inflammation that resolved spontaneously within 6 months was reported in 7.1% of cases (n=3). Implant failure with loss of fracture reduction was reported in 9.5% of cases (n=4).

Conclusions: Newer absorbable materials (PLA or PLA/PGA) appear to have significantly lower rates of noninfectious inflammatory reaction than previously reported. When compared to metallic fixation of the metacarpal shaft, absorbable fixation appears to have comparable complication rates and biomechanical properties.