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Page 12 of 14 Pinnamaneni et al. J Cancer Metastasis Treat 2021;7:7 I http://dx.doi.org/10.20517/2394-4722.2020.94

completed, the humeral length of the resected native humerus should be measured. The osteotomy should
be completed in either a transverse fashion or a step-wise fashion. Next, the humerus allograft should be
prepped on the back table. The allograft should be tailored and cut to fit the native humeral osteotomy. It
is important to have adequate length of the allograft humeral height to maintain adequate tension of the
repaired soft-tissue structures. Next, the allograft should be prepped on the back table using the implant
system of choice. The allograft should be prepped according to the appropriate broaches and reamers to
accommodate the chosen implant. At this point, if a RTSA is being completed, the glenosphere should
be placed. In the case of using a RTSA, adequate lateralization and standard glenosphere placement
techniques should be used. Since these patients are at a higher risk for instability when compared to
non-oncology patients, techniques to increases stability of the RTSA should be used including increased
lateralization of the glenosphere, placement of a larger glenosphere, and using a constraint humeral insert.
Next, the implant with the appropriate humeral stem implant should be implanted into the allograft. The
implant should be long enough to incorporate approximately two cortical diameters distal to the native
humeral osteotomy site. Next, the distal portion of the implant should be placed into the native humeral
canal. Cement techniques should be used to fix the distal portion of the implant into the native humeral
canal. Prior to final cementation, the humeral length and soft-tissue tensioning should be trailed using
a trial prosthesis. Then, the distal portion of the implant is cemented into the native humeral bone. The
decision to place a supplementary plate can be made at the discretion of the surgeon [Figure 5]. A locking
compression plate can be used for fixation. This fixation can be supplemented with an additional anterior
based short plate. Next, the posterior, inferior, and anterior glenohumeral native capsule should be repaired
to the allograft capsule with non-absorbable suture. The host rotator cuff should be repaired to the allograft
rotator cuff attachments. Next, the remaining resected muscles can be attached including the latissimus
dorsi, teres major, pec major, deltoid, etc. Finally, the remaining superficial soft-tissue structures can be
closed.

Postoperatively, the patient is placed in a sling. Initially, the patient is non-weightbearing and range of
motion to the shoulder is limited. Active assisted shoulder range of motion can be initiated after the first
week. Once healing of the allograft-host interface is noted to be adequate, weightbearing can progressively
increased.

Advantages [Table 6]: The advantages of this type of reconstruction include anatomic restoration of the
bone stock, glenohumeral joint, and surrounding soft tissues. This reconstruction option allows for host-
to-graft soft-tissue attachments to attach host tendons, including the latissimus dorsi, deltoid, rotator
[11]
cuff, etc . Over time, the soft-tissue attachments and bony components of the allograft can be fully
incorporated into the host bone and soft tissues over time, unlike with a prosthesis. Additionally, this
reconstruction method can address any pre-existing glenohumeral arthrosis. Placement of standard
hemiarthroplasty or RTSA implants can be used which allows for more modularity and lower cost. The
patient also gets immediate stability and early functionality of the shoulder compared to an osteoarticular
allograft.

Disadvantages [Table 6]: The disadvantages include allograft-related complications including allograft osteolysis,
non-union [Figures 2 and 8], hardware failure, allograft fracture, allograft resorption, stress shielding, and
[24]
delayed union . Additionally, instability, aseptic loosening, and proximal migration [Figures 6 and 7]
[25]
should be considered . Availability of tissue banks and variety of allograft options to include soft-tissue
attachments and enough resected bone stock can be variable depending on geographic location.

Outcomes: A case series of 36 patients treated with APC with an average follow-up of six years showed that
[25]
the average MSTS score at the last follow-up was 26 out of 30 points with an 88% survivorship at 10 years .
Reconstruction with RTSA has shown good functional outcomes as well, with mean MSTS scores reported