1. The healing of the radius and tibia in dogs after compression plating of osteotomies made by a Gigli saw was studied.

2. The methods used were indian ink microangiography and terramycin labelling. The Spalteholz technique and azane colouring were used.

3. Revascularisaton of the fracture region took place both from newly formed vessels in the Haversian systems and from periosteal and endosteal vessels.

4. The fracture gap was filled at an early stage by a vascular network. Under stable conditions direct angiogenic bone formation took place around this network.

5. Rebuilding of the cortical bone in the fracture region occurred by osteoclastic activity. Groups of osteoclasts made cavities in the necrotic bone and were immediately followed by loops of vessels; behind and around the loop new bone was formed. Another form of bone absorption consisted of bundles of vessels which eroded necrotic cortical bone without new bone formation.

6. The new bone was initially oriented along the fracture gap but, by conversion into secondary osteones, it became progressively oriented longitudinally in the direction of the original bone.

7. Under stable conditions some periosteal and endosteal callus formation occurred though it was of slight importance. It regressed very soon and was seldom seen in the radiographs.

In the assessment of fracture healing by monitoring stiffness with vibrational analysis or instrumented external fixators, it has been assumed that there is a workable correlation between stiffness and strength. We used four-point bending tests to study time-related changes in stiffness and strength in healing tibial fractures in sheep. We aimed to test the validity of the measurement of stiffness to assess fracture strength.

At each duration of healing examined, we found marked variations in stiffness and strength. Stiffness was shown to be load-dependent: measurements at higher loads reflected ultimate strength more accurately. There was a biphasic relationship between stiffness and strength: at first there was a strong correlation regardless of loading conditions, but in the second phase, which included the period of ‘clinical healing’, stiffness and strength were not significantly correlated.

We conclude that the monitoring of stiffness is useful primarily in assessing progress towards union but is inherently limited as an assessment of strength at the time of clinical union. Any interpretation of stiffness must take into account the load conditions.

1. Clinical studies in humans have indicated that a delay of one to three weeks in the open reduction of a fracture decreases the incidence of delayed union and non-union.

2. Studies in cats indicate that a delay of two weeks before open reduction causes a different repair mechanism from that following immediate operation.

3. Repair after delayed operation is characterised by increased periosteal new bone formation and more rapid endochondral bone formation. After immediate operation periosteal new bone is slow to develop; much more fibrous tissue and cartilage develop, followed by slow endochondral bone formation.

Methods

Between 2005 and 2012, 50 patients (23 female, 27 male) with nonunion of the humeral shaft were included in this retrospective study. The mean age was 51.3 years (14 to 88). The patients had a mean of 1.5 prior operations (sd 1.2;1 to 8).

All patients were assessed according to a specific risk score in order to devise an optimal and individual therapy plan consistent with the Diamond Concept. In 32 cases (64%), a change in the osteosynthesis to an angular stable locking compression plate was performed. According to the individual risk an additional bone graft and/or bone morphogenetic protein-7 (BMP-7) were applied.

Five consecutive unstable fractures of the distal third of the clavicle were treated by indirect open reduction and internal fixation using a temporary Bosworth-type screw. Coracoclavicular fixation provided and maintained reduction of the fracture. Healing occurred uneventfully within nine weeks in all cases. The screw was removed under local anaesthesia after healing of the fracture and there were no surgical complications. Shoulder function was restored to the pre-injury level. Temporary coracoclavicular screw fixation appears to be a valuable alternative for the treatment of type II fractures of the distal third of the clavicle

Aims

To evaluate whether low-intensity pulsed ultrasound (LIPUS) accelerates bone healing at osteotomy sites and promotes functional recovery after open-wedge high tibial osteotomy (OWHTO).

The objective of this study was to validate the efficacy of Takeuchi classification for lateral hinge fractures (LHFs) in open wedge high tibial osteotomy (OWHTO). In all 74 osteoarthritic knees (58 females, 16 males; mean age 62.9 years, standard deviation 7.5, 42 to 77) were treated with OWHTO using a TomoFix plate. The knees were divided into non-fracture (59 knees) and LHF (15 knees) groups, and the LHF group was further divided into Takeuchi types I, II, and III (seven, two, and six knees, respectively). The outcomes were assessed pre-operatively and one year after OWHTO. Pre-operative characteristics (age, gender and body mass index) showed no significant difference between the two groups. The mean Japanese Orthopaedic Association score was significantly improved one year after operation regardless of the presence or absence of LHF (p = 0.0015, p < 0.001, respectively). However, six of seven type I cases had no LHF-related complications; both type II cases had delayed union; and of six type III cases, two had delayed union with correction loss and one had overcorrection. These results suggest that Takeuchi type II and III LHFs are structurally unstable compared with type I.

Cite this article: Bone Joint J 2015;97-B:1226–31.