Fifth metatarsal stress fracture is the one of the most common injury in soccer.
In order to clarify the characteristics of simple radiographic images of Jones fractures and the factors affecting postoperative results, we investigated and reviewed the cases of intramedullary screw fixation performed at our hospital in recent years. We hypothesized that different positions may cause different fracture sites, especially in soccer players who are prone to this type of fracture.
Subjects and Methods
From April 1, 2006 to December 31, 2021, 110 feet of 103 patients with Jones fractures treated at our hospital were investigated. From review of medical records and questionnaires, age at injury, date of injury, date of return to sport, type of sport were investigated. For soccer players, we checked position and dominant foot.
The metatarsal length, screw length, and the distance from the proximal end to the fracture site were measured from simple oblique radiographic images. The ratio of screw length to the total length of the fifth metatarsal (Screw/Metatarsal ratio, hereafter referred to as S/M ratio) and the ratio of the length of the screw distal to the fracture site (Distal/Proximal ratio, hereafter referred to as D/P ratio) were measured.
Follow-up simple radiographs were taken to determine the time to bridging callus, time to bone healing, and time to return to sport. Cases with prolonged bone healing and those requiring more than 6 months to return to sport were defined as poor postoperative outcome cases.
Results
The sports that caused fractures in 103 patients were soccer (81), futsal (2), basketball (10), rugby (2), and baseball (2). The average age at the time of injury was 18.6 years, with 17 years being the most common age. Eighty-four patients were available for follow-up, and it took an average of 6.5 weeks for temporary bone formation, 13.4 weeks for bone fusion, and 14.0 weeks for return to sport. Eight cases (9.5%) of poor postoperative outcome cases were observed. The mean length of the fifth metatarsal bone was 81.2 mm, and the fracture was located 35.6% (28.7 mm) from the proximal end. The mean S/M ratio was 0.6 and the mean D/P ratio was 0.9.
Comparing the poor postoperative outcome cases with other cases, the D/P ratio was significantly lower in the poor postoperative outcome cases, with a mean of 0.72 (p=0.04).
In soccer players, fracture site tended to be more distal in outside players than in central players (p=0.054), and the position of the fracture tended to be more distal in the pivot foot of outside players (p=0.08).
Conclusions
Postoperative results were influenced by the athlete's athletic level and postoperative treatment. The D/P ratio was significantly lower in the poor postoperative outcome cases.