Mapping recovery in simple and complex tibial plateau fracture fixation

Aims

The aim of this study was to determine the trajectory of recovery following fixation of tibial plateau fractures up to five-year follow-up, including simple (Schatzker I-IV) versus complex (Schatzker V-VI) fractures.

Patients and Methods

Patients undergoing open reduction and internal fixation (ORIF) for tibial plateau fractures were enrolled into a prospective database. Functional outcome, using the 36-Item Short Form Health Survey Physical Component Summary (SF-36 PCS), was collected at baseline, six months, one year, and five years. The trajectory of recovery for complex fractures (Schatzker V and VI) was compared with simple fractures (Schatzker I to IV). Minimal clinically important difference (MCID) was calculated between timepoints. In all, 182 patients were enrolled: 136 (74.7%) in simple and 46 (25.3%) in complex. There were 103 female patients and 79 male patients with a mean age of 45.8 years (15 to 86).

Results

Mean SF-36 PCS improved significantly in both groups from six to 12 months (p < 0.001) and one to five years (simple, p = 0.008; complex, p = 0.007). In both groups, the baseline scores were not reached at five years. The SF-36 PCS was significantly higher in the simple group compared with the complex group at both six months (p = 0.007) and 12 months (p = 0.01), but not at five years (p = 0.17). Between each timepoint, approximately 50% or more of the patients in each group achieved an MCID in their score change, indicating a significant clinical change in condition. The complex group had a much larger drop off in the first six months, with comparable proportions achieving MCID at the subsequent time intervals.

Conclusion

Tibial plateau fracture recovery was characterized overall by an initial decline in functional outcome from baseline, followed by a steep improvement from six to 12 months, and ongoing recovery up to five years. In simple patterns, patients tended to achieve a higher functional score by six months compared with the complex patterns. However, comparable functional scores between the groups achieved only at the five-year point suggest later recovery in the complex group. Function does not improve to baseline by five years in either group. This information is useful in counselling patients about the course of prospective recovery. Cite this article: Bone Joint J 2019;101-B:1009–1014.

Interpretation of Post-operative Distal Humerus Radiographs After Internal Fixation: Prediction of Later Loss of Fixation

PURPOSE

Stable fixation of distal humerus fracture fragments is necessary for adequate healing and maintenance of reduction. The purpose of this study was to measure the reliability and accuracy of interpretation of postoperative radiographs to predict which implants will loosen or break after operative treatment of bicolumnar distal humerus fractures. We also addressed agreement among surgeons regarding which fracture fixation will loosen or break and the influence of years in independent practice, location of practice, and so forth.

METHODS

A total of 232 orthopedic residents and surgeons from around the world evaluated 24 anteroposterior and lateral radiographs of distal humerus fractures on a Web-based platform to predict which implants would loosen or break. Agreement among observers was measured using the multi-rater kappa measure.

RESULTS

The sensitivity of prediction of failure of fixation of distal humerus fracture on radiographs was 63%, specificity was 53%, positive predictive value was 36%, the negative predictive value was 78%, and accuracy was 56%. There was fair interobserver agreement (κ = 0.27) regarding predictions of failure of fixation of distal humerus fracture on radiographs. Interobserver variability did not change when assessed for the various subgroups.

CONCLUSIONS

When experienced and skilled surgeons perform fixation of type C distal humerus fracture, the immediate postoperative radiograph is not predictive of fixation failure. Reoperation based on the probability of failure might not be advisable.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

Early fixation of the vertically unstable pelvis: the role of iliosacral screw fixation of the posterior lesion

OBJECTIVES

To evaluate the effectiveness of the use of iliosacral screw fixation in the management of the vertically unstable pelvis.

STUDY DESIGN

Retrospective analysis with clinical follow-up of patients to assess functional outcome.

METHODS

Thirty-eight vertically unstable pelvic fractures were treated using iliosacral screw fixation. Anterior fixation was by means of plating in sixteen pelves and by external fixation in fifteen pelves. Four pelves had no anterior fixation. Complications were recorded and radiographs were analyzed to classify fractures and identify screw misplacement and malunion. Twenty-six patients had a functional evaluation.

RESULTS

Five patients (13 percent) suffered a pulmonary embolus in the early postoperative period, one of which was fatal, a hospital mortality of 2.6 percent. Screw misplacement occurred in five patients but there were no adverse sequelae. In thirty-four cases with radiographic follow-up, malunion was noted in fifteen cases (44 percent). A lower rate of malunion (36 percent) was noted with internal fixation of the anterior lesion. Of twenty-six patients with long-term follow-up, only four (15 percent) had no pain. Sacroiliac fusion for pain was performed in three patients (11 percent). Twelve patients (46 percent) returned to their preinjury occupation, six patients (23 percent) changed occupation, and nine patients (30 percent) had not yet returned to work by last follow-up.

CONCLUSIONS

Iliosacral screw fixation is a useful method of fixation in the vertically unstable pelvis but needs to be augmented by rigid anterior fixation to minimize malunion.

Reamed nailing of open tibial fractures: does the antibiotic bead pouch reduce the deep infection rate?

Eighty-one open tibial fractures were treated by reamed intramedullary nailing. There were 38 type II, 23 type IIIa and 20 type IIIb injuries. At the end of the nailing procedure the first 26 fractures (15 type II, five type IIIa, and six type IIIb) had antibiotic prophylaxis and delayed closure of the open wound. The subsequent 55 fractures (23 type II, 18 type IIIa, and 14 type IIIb) had identical management but in addition had an antibiotic bead pouch inserted into the open wound following debridement. Three amputations were performed: one (3.8%) in the group treated without a bead pouch and two (3.6%) in the bead pouch group in patients with grade IIIb fractures and severe crushing injuries. Of the remainder, there were four deep infections (16%) in the 25 fractures treated prior to the use of the bead pouch and two (4%) deep infections in the 53 fractures following introduction of the bead pouch. Addition of the bead pouch to the wound management protocol was associated with a worthwhile reduction of deep infection.

Proteoglycans synthesized by cultured mouse osteoblasts

Proteoglycan synthesis in nonmineralizing osteoblast cultures was investigated. Cultures were labeled with [35S]sulfate or [3H]serine, and proteoglycans were extracted from medium and cell layer with 4 M guanidine HCl. Labeled material was subjected to Sepharose CL-4B and DEAE-Sephacel chromatography and polyacrylamide gel electrophoresis. The size and composition of the glycosaminoglycan chains and the protein core size were determined. Two proteoglycan populations were isolated by Sepharose CL-4B chromatography: a minor excluded species with chondroitin sulfate chains of apparent Mr 25,000 and a smaller population (Kav = 0.43) accounting for 80% of the total labeled material. This small population resolved into two species by polyacrylamide gel electrophoresis. Both species contain dermatan sulfate chains of apparent Mr 40,000 and a core protein with Mr 45,000 on sodium dodecyl sulfate gels. With the exception of their glycosaminoglycan composition these species appear similar to those extracted from bone. In addition, high molecular weight hyaluronic acid and glycosaminoglycan peptides were found in cell extracts.

Glucose and insulin dynamics in the anaesthetized dog: a mathematical modeling study

A combined circulation and organs model of glucose and insulin dynamics is presented. The model is based on physiological parameters, incorporating blood and plasma flow rates, circulatory paths, intra-and extra-vascular glucose and insulin spaces, as well as the specific organs and tissues involved both with insulin disappearance and with glucose production or uptake. Its simulations readily lend themselves to physiological interpretation. To explore its validity, the model was assigned parameters typical of a 12 kg dog and was arranged to accept known glucose and insulin infusions from four different experiments on such diabetic animals. It predicted the observed glucose and insulin concentrations as well as total uptake rates for both moieties. This confirmed the ability of the model to predict with consistency the group mean outcomes of these four experiments when differing routes (portal or peripheral) of infusion were applied. Excellent agreement for most studies was achieved while the need for including more sophisticated dynamics of glucose transport in the liver or into erythrocytes was identified. The model isolates glucose uptake in the periphery, the liver, the brain and the gut and allows a direct comparison of glucose disposal along various routes. Thus the total amount of glucose uptake by peripheral, insulin-dependent tissues is directly calculated to be 22-28% of an intravenous glucose load, regardless of its route of infusion.