The majority of periprosthetic fractures of the greater tuberosity , type A according to the Worland classification, are stable [19]. They are usually non- or minimally displaced and, when occurring postoperatively, can be managed nonoperatively (immobilization in a sling or brace for about 4 weeks) with symptomatic treatment. Intraoperative stable fractures of the greater tuberosity can be managed similarly. Displaced, or otherwise unstable, intraoperative fractures are generally treated with a cerclage. Intraoperative fractures of the tuberosities have been considerably diminished by having the availability of trial humeral stems without associated heads that can be maintained in the humeral canal during posterior retraction of the proximal humerus during glenoid preparation. If there is an osteopenic bone condition that could weaken the greater and lesser tuberosity, it may be useful to perform a transdeltoid surgical exposure rather than a deltopectoral approach to avoid torsional stress on the tuberosities during performance of the procedure.

The Worland type C fractures are defined as being “distal” to the humeral stem. The literature demonstrates that these fractures with a well-fixed humeral component are similar to closed humerus fractures and may respond favorably to nonoperative treatment. Campbell et al. [13] reported on a multicenter series of periprosthetic humeral fractures. Each of the five postoperative fractures healed with nonoperative management. Four of these were distal to the tip of the humeral stem. When the humeral component of the prosthesis is loose, revision with a longer stemmed humeral component is the first choice. In case an acceptable closed reduction cannot be obtained with the use of a plastic orthosis, an open reduction and internal fixation (ORIF) could be considered. General principles are anatomic reduction and a stable fixation using a long plate to overlap the humeral stem. Fixation in the distal fragment is with multiple bicortical screws distal to the stem into the native bone and mono-cortical screws in the zone of the humeral prosthesis supplemented with multiple cables. Similar systems are generally used for periprosthetic fractures of the femur [5–8, 11–15, 26, 27].

Bone graft is also used in order to maximize the healing potential: allograft in acute cases and autograft (iliac crest) in cases with delayed healing or nonunion. In addition, one may consider supplementary fixation with a cortical strut onlay allograft in combination with a plate and screws/cables to obtain secure fixation. The specific revision strategy chosen depends on the quality of the remaining bone stock [28, 29].

In case of a periprosthetic humeral fracture with a loosening component, several strategies can be used, but all rely on obtaining secure distal fixation [30]. Only rarely a cemented long-stem component is used; the most effective strategies include noncemented distal fixation techniques. If the distal fragment maintains 5 cm of intact tubular diaphysis, then extensively coated uncemented long-stem prosthesis with or without plate augmentation could be used (Figs. 22.2, 22.3, and 22.4). The distal canal is reamed, and a trial stem is temporarily implanted. The proximal fragments can then be reduced using the trial component as a template. A lateral plate with cerclage cables is then applied in order to recover the normal length and obtain a stable fixation. Once length and stability are acceptable, the trial component is removed, and a definitive humeral stem is impacted; the cerclage cables are then retensioned and cut, and some screws are added to maximize the stability. The appropriate humeral length is selected combining different modular components (metaphysis and head), and a trial reduction is performed. After trialing, the definitive components are assembled and the shoulder reduction. These types of modular prosthesis have demonstrated excellent results in the revision setting and for periprosthetic fracture situations [30, 31]. This strategy is also effective for the Worland type B3 fractures (fractures about the prosthesis with an unstable stem).

Rarely, the proximal bone is so deficient that a modular proximal humeral replacement (so-called tumor prosthesis) could be used. In these situations, a cemented distal fixation is recommended. The proximal remaining bone and soft tissue can be cerclaged around the body of the proximal humeral replacing prosthesis with cable or heavy braided suture in order to maintain a stable shoulder.

For the Worland type B1 and B2 fractures with good alignment and a well-fixed humeral component, a nonoperative treatment could be considered. However, as reported in the literature, type B fractures treated nonoperatively have a high propensity to fail to heal and eventually require surgery. Wright and Cofield suggested that operative treatment should be considered for short oblique or transverse fractures that occur at the level of prosthesis tip. In addition, they recommended the use of autologous bone graft at the time of surgery. Type B fractures that have not progressed toward union by 3 months are also recommended for operative intervention.

For patients with a type B fracture and a well-fixed humeral component, the preferred current construct practice is a lateral plate with screw fixation in the distal portion and cerclage fixation in the proximal portion of the humerus. Distally, the plate should have a minimum of four to six holes covering the native humerus distal to the stem. If the diaphyseal bone is osteoporotic, as it is in many cases of periprosthetic fractures, locked screws are indicated. Locked screws should be placed after non-locked screws and appear to be most advantageous near the fracture site. Two or three equally spaced cables are used proximally between the surgical neck and the tip of the stem. The cables are sequentially tightened akin to the method of tightening a car wheel. This assures that tightening one cable does not result in loosening of an adjacent cable. Bone grafts are also used in order to maximize the healing potential, and strut allografts are reserved for situations with associated bone loss. The strut is secured with cables independent of an associated plate (cables over the strut and under the plate) and with cables around both.

The occurrence of humeral fractures after a shoulder prosthesis does not appear to significantly alter the final functional results.

Fractures of the glenoid usually occur intraoperatively when the glenoid is extremely osteopenic, such as in the patient with rheumatoid arthritis, and are related to the reaming or fixation technique. These complications concern only total shoulder replacements. Generally, the fracture fragments are small and comminuted and are not available to screw fixation. With inadequate bone support, the implant of a glenoid component should be abandoned and the defect bone grafted for a two-stage revision. After fracture healing, conversion of a hemiarthroplasty to a total unconstrained or RSA can be considered if symptoms require.

Postoperative acromial and spine fractures after RSA and their treatment have been described in the literature [32–35]. Because of the relatively brief history of the RSA, the management of these complications is poorly understood. The operative treatment is characterized by a high rate of nonunion due to the difficulty of stabilizing an osteoporotic bone under the increased tension of an elongated deltoid. The natural history of nonoperative management is characterized by reduced global shoulder function, but most of the patients who experienced this complication did not report chronic pain [36]. Given these patient outcomes, conservative treatment with an abduction splint for 6 weeks to limit pain and acromial tilt is a reasonable option for this complication.