Refixation tibialer knöcherner Avulsionsverletzungen des hinteren Kreuzbandes in Fadenankertechnik

[Treatment of Injuries to the Posterior Cruciate Ligament]

Compared to the anterior cruciate ligament injury, the rupture of the posterior cruciate Ligament (PCL) is the rarer condition. A high healing potential is attributed to the PCL in the literature, which is why conservative therapy is also considered important in addition to surgical treatment 1. Posterior cruciate ligament rupture is often associated with concomitant injuries. Among other things, up to 70% of cases are associated with accompanying injuries to the posterolateral corner 2. The detection of concomitant injuries has a significant influence on the outcome, as isolated surgical PCL stabilization does not lead to satisfactory results in these cases.

Biomechanical study of posterior cruciate ligament tibial arrest avulsion fracture fixation with triple tibial channel net sutures

To investigate the biomechanical properties of posterior cruciate ligament avulsion fractures of the tibia fixed using four different methods, including triple tibial channel net suture fixation. In 40 porcine knees, a standardized bony avulsion of the posterior cruciate ligament was generated. Double tibial bone channel suture fixation was performed in group A, double-head hollow compression screw fixation was performed in group B, triple tibial bone channel net suture fixation was performed in group C, and cortical suspension EndoButton fixation was performed in group D. The constructs were cyclically loaded 500 times (10 to 100 N) to measure the initial displacement and stiffness values. Subsequently, loading to failure was performed, and the yield load and peak load were measured. The results were analysed by one-way ANOVA, with significance set at P < 0.05. The initial displacement in group D (1.00 ± 0.20 mm) was lower than that in group C (1.46 ± 0.33 mm, P = 0.000), group B (1.91 ± 1.71 mm, P = 0.000) and group A (3.91 ± 0.79 mm, P = 0.000), but there was no significant difference between groups B and C (P = 0.055). The initial stiffness in group A (50.59 ± 6.89 N/mm) was lower than that in group C (67.21 ± 12.80 N/mm, P = 0.001), group D (71.18 ± 9.20 N/mm, P = 0.000) and group B (78.67 ± 5.91 N/mm, P = 0.000). However, there was no significant difference between groups B and D or between groups C and D (P = 0.111 and P = 0.391). The yield load in group A (554.86 ± 71.43 N) was lower than that in group C (767.00 ± 34.53 N, P = 0.000), group D (777.62 ± 73.03 N, P = 0.000) and group B (837.50 ± 55.73 N, P = 0.000). There was no significant difference between groups C and D (P = 0.729). The peak load in group A (667.38 ± 61.54 N) was lower than that in group C (842.00 ± 26.20 N, P = 0.000), group D (867.63 ± 63.42 N, P = 0.000) and group B (901.25 ± 54.38 N, P = 0.000). There was no significant difference between groups C and D (P = 0.346). Different failure modes were found among the four groups. The triple tibial bone channel suture fixation group showed better initial stability and fixation strength, which was comparable to that in the cortical suspension EndoButton fixation group and double-head hollow compression screw fixation group and significantly stronger than that in the double tibial bone channel suture fixation group. This study analysed the dynamic and static indexes of posterior cruciate ligament tibial avulsion fractures fixed by four different fixation methods under cyclic loading tests and single failure loading tests, providing a theoretical basis for clinical treatment.

Treatment of avulsion fracture of posterior cruciate ligament tibial insertion by minimally invasive approach in posterior medial knee

Objective

The study aims to explore the feasibility and clinical effect of posterior minimally invasive treatment of cruciate ligament tibial avulsion fracture.

Methods

Posterior knee minimally invasive approach was used to treat avulsion fracture of posterior cruciate ligament (PCL) tibia in 15 males and 11 females. The length of the incision, intraoperative blood loss, operation time, postoperative hospital stay, residual relaxation, and fracture healing time were analyzed to evaluate the curative effect, learning curve, and advantages of the new technology. Neurovascular complications were recorded. During the postoperative follow-up, the International Knee Joint Documentation Committee (IKDC), Lysholm knee joint score, and knee joint range of motion were recorded to evaluate the function.

Results

All 26 patients were followed up for 18-24 months, with an average of 24.42 ± 5.00 months. The incision length was 3-6 cm, with an average of 4.04 ± 0.82 cm. The intraoperative blood loss was about 45-60 ml, with an average of 48.85 ± 5.88 ml. The operation time was 39-64 min, with an average of 52.46 ± 7.64 min. The postoperative hospital stay was 2-5 days, with an average of 2.73 ± 0.87 days. All incisions healed grade I without neurovascular injury. All fractures healed well with an average healing time of 9.46 ± 1.33 weeks (range, 8-12 weeks). The Lysholm score of the affected knee was 89-98 (mean, 94.12 ± 2.49) at 12-month follow-up. The IKDC score was 87-95 with an average of 91.85 ± 2.19, and the knee range of motion was 129-148° with an average of 137.08 ± 5.59°. The residual relaxation was 1-3 mm, with an average of 1.46 ± 0.65 mm.

Conclusion

This minimally invasive method provides sufficient exposure for internal fixation of PCL tibial avulsion fractures without the surgical complications associated with traditional open surgical methods. The process is safe, less invasive, and does not require a long learning curve.

Open reduction and internal fixation of the tibial avulsion fracture of the posterior cruciate ligament: which is better, a hollow lag screw combined with a gasket or a homemade hook plate?

OBJECTIVE

To compare the clinical results of homemade hook plates and hollow lag screws combined with spacers in the treatment of posterior cruciate tibial ligament avulsion fractures.

MATERIALS AND METHODS

This was a retrospective clinical cohort study that included 64 patients with PCL tibial avulsion fractures. Thirty-two of them were fixed with a homemade hook plate (hook plate group), and 32 were fixed with a hollow lag screen combined with a gasket (hollow lag screen group). By reviewing the medical record data and follow-up results, the operation time, postoperative drainage, fracture healing time, surgical complications, knee mobility, recovery of joint function, and whether postoperative gastrocnemius muscle strength changed in the two groups were compared.

RESULTS

All patients had successful wound and fracture healing. No adverse events, such as bone nonunion, infection, wound haematoma, or joint stiffness, occurred in either group. There were no patients with decreased gastrocnemius muscle strength in either group. Internal fixation failure occurred in 2 cases in the hollow lag screen group but not in the hook plate group. There were no significant differences between the two groups in terms of operative time, postoperative drainage, fracture healing time, knee mobility at the last follow-up, or Lysholm score.

CONCLUSION

It is safe and effective to use a homemade hook plate to fix PCL tibial avulsion fractures through an inverted L-shaped posterior medial approach. A homemade hook plate may have potential advantages over a hollow lag screen combined with gasket fixation.

Outcomes of tibial avulsion fracture of the posterior cruciate ligament treated with a homemade hook plate

OBJECTIVE

To compare the clinical effects of an inverted L-shaped postero-medial approach with a homemade hook plate and arthroscopic fixation with Endobutton for tibial avulsion fractures of the posterior cruciate ligament.

METHODS

The clinical data of 36 patients with PCL tibial avulsion fractures from January 2012 to December 2019 were analyzed retrospectively. The fractures were classified into Meyers-McKeever types II and III. Among them, 20 cases were treated with a homemade hook plate through an inverted L-shaped postero-medial approach (incision group), and 16 cases were treated with Endobutton under arthroscopy (arthroscopic group). The operative time, fracture union time, operative complications and range of motion of the knee joint were compared between the two groups. The stability of the knee joint was tested by the posterior drawer test, the functional recovery of the knee joint was evaluated by the Lysholm score, and the gastrocnemius muscle strength of the incision group was tested by performing heel raises with a single leg stance.

RESULTS

There were no adverse events, such as fracture nonunion, infection, deep-vein thrombosis, abnormal hematoma or joint stiffness, in either group. The operative time was shorter in the incision group, and the difference was statistically significant (P < 0.05). There was no significant difference in fracture union time between the two groups (P > 0.05). At the last follow-up, there was no significant difference in range of motion or the Lysholm score between the two groups. There was no decrease in gastrocnemius muscle strength in the incision group.

CONCLUSIONS

The fixation of PCL tibial avulsion fractures with a homemade hook plate through an inverted L-shaped postero-medial approach is safe and effective. It showed almost the same satisfactory outcomes as arthroscopic Endobutton fixation.

Suspension button constructs restore posterior knee laxity in solid tibial avulsion of the posterior cruciate ligament

PURPOSE

Dislocated tibial avulsions of the posterior cruciate ligament (PCL) require surgical intervention. Several arthroscopic strategies are options to fix the fragment and restore posterior laxity, including two types of suspension button devices: adjustable (self-locking) and rigid knotted systems. Our hypothesis was that a rigid knotted button construct has superior biomechanical properties regarding laxity restoration compared with an adjustable system. Both techniques were compared with standard screw fixation and the native PCL.

METHODS

Sixty porcine knees were dissected. The constructs were tested for elongation, stiffness, yield force, load to failure force, and failure mode in a material testing machine. Group N (native, intact PCL) was used as a control group. In group DB (Dogbone™), TR (Tightrope™), and S (screw), a standardized block osteotomy with the osteotomized fragment attached to the PCL was set. The DB and TR groups simulated using a suspension button system with either a rigid knotted (DB) or adjustable system (TR). These groups were compared to a screw technique (S) simulating antegrade screw fixation from posterior.

RESULTS

Comparing the different techniques (DB, TR, S), no significant elongation was detected; all techniques achieved a sufficient posterior laxity restoration. Significant elongation in the DB and TR group was detected compared with the native PCL (N). In contrast, screw fixation did not lead to significant elongation. The stiffness, yield load, and load to failure force did not differ significantly between the techniques. None of the techniques reached the same level of yield load and load to failure force as the intact state.

CONCLUSION

Arthroscopic suspension button techniques sufficiently restore the posterior laxity and gain a comparable construct strength as an open antegrade screw fixation.

[All-arthroscopic fixation of tibial posterior cruciate ligament avulsion fractures with a suture-button technique]

OBJECTIVE

To restore the posterior stability of the knee after a tibial posterior cruciate ligament (PCL) avulsion with a suture-button construct.

INDICATIONS

Acute solid and monofragment bony avulsion of the tibial PCL insertion.

CONTRAINDICATIONS

Chronic condition of avulsion fractures or posterior instability, multifragment avulsions, thin bone pieces, advanced knee osteoarthritis, high-grade soft tissue injury, infection.

SURGICAL TECHNIQUE

Supine position, all-arthroscopic treatment via posteromedial and posterolateral portal, arthroscopic visualization and fracture reduction, transtibial drilling with a cannulated 2.4 mm drill, reduction of the fragment via FiberTape™ and Dog Bone. Knotting of the tapes against an additional Dog Bone at the anterior aspect of the tibia. Intraoperative x‑ray.

POSTOPERATIVE MANAGEMENT

Knee extension brace with posterior tibial support for 6 weeks, 20 kg partial weight-bearing and restricted flexion up to 90° for 6 weeks, physiotherapy in prone position from the first postoperative day. Full weight bearing after x‑ray and clinical control after 6 weeks.

RESULTS

Since 2016 eight tibial PCL avulsions were treated. In 6 patients a suture-bridge technique via a mini-open approach was performed due to a small or comminuted fracture fragment. In 2 patients an all-arthroscopic technique was performed. No complications. The all-arthroscopic technique requires a solid fragment and enables the surgeon to treat additional pathologies. In general, the arthroscopic technique makes the open posterior approach unnecessary. The arthroscopic techniques achieve slightly higher objective and subjective values compared to the open procedure, despite a higher rate of arthrofibrosis.