Discussion: Intramedullary Screw Fixation of Metacarpal Fractures Results in Excellent Functional Outcomes

Expanding the applications of intramedullary cannulated screw fixation in the hand

OBJECTIVES

Intramedullary cannulated headless compression screw fixation (ICHCS) is gaining popularity for managing metacarpal and phalangeal fractures, but is still relatively new to the surgical landscape. We aim to further illustrate its utility and versatility by presenting the outcomes of such fractures treated with ICHCS at two tertiary plastic surgery centres. Primary objectives were to assess functional range of motion, patient-reported outcomes, and complication rates.

MATERIALS AND METHODS

All patients with metacarpal or phalangeal fractures treated with ICHCS (n = 49) between September 2018 and December 2020 were retrospectively reviewed. Outcomes were active ranges of motion (TAM), QuickDASH scores (obtained via telephone), and complication rates. Two-tailed Student's t-tests evaluated differences between centres.

RESULTS

TAMs were available for 59% (n = 34/58) of fractures; 70.7% were metacarpal and 29.3% were phalangeal. The mean cohort metacarpal TAMs and phalangeal TAMs were 237.7° and 234.5°, respectively. QuickDASH scores were available for 69% (n = 34/49) of patients. The mean cohort score for metacarpal fractures was 8.23, and 5.13 for phalangeal. Differences between the two centres were statistically significant (p < 0.05). Two complications occurred, giving an overall complication rate of 3.45%.

CONCLUSION

Our results corroborate previous reports on ICHCS, further demonstrating its versatility and capacity to provide excellent outcomes. More prospective, comparative studies are needed to fully determine the suitability of ICHCS.

Biomechanical comparison of intramedullary screw fixation, dorsal plating and K-wire fixation for stable metacarpal shaft fractures

We compared four methods of metacarpal shaft fixation: 2.2 mm intramedullary headless compression screw; 3.0 mm intramedullary headless compression screw; intramedullary K-wire fixation; and dorsal plate fixation. Transverse mid-diaphyseal fractures were created in 64 metacarpal sawbones and were assigned into four groups. Peak load to failure and stiffness were measured in cantilever bending and torsion. We found that dorsal plating had the highest peak load to failure. However, initial bending stiffness of the 3.0 mm intramedullary headless compression screw was higher than that of the dorsal plates. In torsion testing, dorsal plating had the highest peak torque, but there was no significant difference in torsional stiffness between the plate and intramedullary headless compression screw constructs. We concluded that intramedullary headless compression screw fixation is biomechanically superior to K-wires in cantilever bending and torsion; however, it is less stable than dorsal plating. In our study, the initial stability provided by K-wire fixation was sufficient to cope with expected loads in the early rehabilitation period, whereas dorsal plates and IHCS constructs provided stability far in excess of what is required.

How to Manage Complications Related to the Use of Intramedullary Screws in Metacarpal Fractures: Case Series

The use of intramedullary screws has been increasing among hand surgeons in cases of metacarpal fractures due to their low morbidity, and because they minimize incisions and dissection, and require less tissue manipulation and deperiostization. However, there are few published articles on the complications that arise from its use. Therefore, the purpose of the current study is to present a series of cases of complications following the use of intramedullary screws in metacarpal fractures that required surgical intervention, and to describe the surgical technique used to solve them .

Methods We performed a retrospective multicenter study in which we reviewed the clinical history, surgical descriptions and radiographs of the patients submitted to fixation of intramedullary compression screws for metacarpal fractures. We defined as complications infection, lesion to the extensor apparatus, bending of the implant, loss of reduction, hardware failure, malrotation, and non-union.

Results Out of a total of 45 patients, we reported 3 cases of complication: 1 patient with loss of reduction, and 2 patients with bending of the implant. In the three cases, the screw was removed without complications, and the focus of the fracture was stabilized.

Conclusion Intramedullary fixation with compression screws is increasingly being used for metacarpal fractures, with reports of low rates of complications. In the series of cases herein reported, the complications were solved without difficulty, and the patients showed a good recovery in hand function in the follow-up. Knowledge of the possible complications and their management enables us to provide more safety to the patient at the time of choosing this technique.

Intramedullary screw fixation of metacarpal and phalangeal fractures - A systematic review of 837 patients

Intramedullary screw (IMS) fixation is increasingly used as an alternative treatment option in metacarpal and phalangeal fractures of the hand. However, this technique is currently the subject of controversy among hand surgeons. The aim of this systematic review was to gain insight on radiological, functional and patient-rated outcomes reported in literature. A comprehensive literature search of PubMed, Embase, CENTRAL and CINAHL databases was conducted on March 1st, 2021. All studies reporting on fracture union, complications, and functional and patient-rated outcome in IMS fixation of metacarpal and/or phalangeal fractures were selected. Two prospective and 16 retrospective cohort studies were included, encompassing a total of 837 patients with 958 fractures (693 metacarpal, 222 proximal phalangeal and 43 middle phalangeal). Mean surgery duration was 26.4 min (range 5-60 min). Union was ultimately achieved in all fractures in a mean of 5.7 weeks (range 2-12 weeks). The procedure-related complication rate was 3.2%. The most frequently reported complication was limitation of joint motion, occurring in 2.0% of cases. Incidence of other complications, including loss of reduction, infection and screw protrusion did not exceed 1%. Overall mean total active motion averaged 243° and grip strength reached 97.5% of the contralateral side. The Disabilities of the Arm, Shoulder and Hand (DASH) score averaged 3.7 points. Duration of sick leave was 7.3 weeks. According to the findings of this systematic review, IMS fixation is a time-saving and safe minimally invasive solution for both metacarpal and phalangeal fractures, with a low rate of complications and promising functional and patient-rated results.